Case Title: Gary Hannemann v. Craig Boyson

Citation: 2005 WI 94

Docket Number: 2003AP001527

State: wisconsin

Court: Wisconsin Supreme Court

Date: 2005-06-29T00:00:00Z

Document:
2005 WI 94 
 
 
 
SUPREME COURT OF WISCONSIN 
 
 
 
 
 
CASE NO.: 
2003AP1527 
COMPLETE TITLE: 
 
 
Gary Hannemann,  
          Plaintiff-Respondent-Petitioner, 
     v. 
Craig Boyson, D.C.,  
          Defendant-Appellant. 
 
 
 
 
REVIEW OF A DECISION OF THE COURT OF APPEALS 
2004 WI App 96 
Reported at:  273 Wis. 2d 457, 681 N.W.2d 561 
(Ct. App. 2004-Published) 
 
 
OPINION FILED: 
June 29, 2005   
SUBMITTED ON BRIEFS: 
        
ORAL ARGUMENT: 
February 2, 2005   
 
 
SOURCE OF APPEAL: 
 
 
COURT: 
Circuit   
 
COUNTY: 
Outagamie   
 
JUDGE: 
Harold V. Froehlich   
 
 
 
JUSTICES: 
 
 
CONCURRED: 
        
 
DISSENTED: 
BUTLER, JR., J., dissents (opinion filed).   
 
NOT PARTICIPATING: PROSSER, J., did not participate.   
 
 
 
ATTORNEYS: 
 
For the plaintiff-respondent-petitioner there were briefs 
by John C. Peterson, Jolene D. Schneider and Peterson, Berk & 
Cross, S.C., Appleton, and oral argument by John C. Peterson. 
 
For the defendant-appellant there was a brief by Thomas R. 
Schrimpf, Patrick F. Koenen, Jeffrey D. Patza, and Hinshaw & 
Culbertson, LLP, Milwaukee, and oral argument by Patrick F. 
Koenen. 
 
2005 WI 94 
 
NOTICE 
This opinion is subject to further 
editing and modification.  The final 
version will appear in the bound 
volume of the official reports.   
No.  2003AP1527  
(L.C. No. 
00 CV 765) 
STATE OF WISCONSIN  
 
 
   : 
IN SUPREME COURT 
 
 
Gary Hannemann,  
 
          Plaintiff-Respondent-Petitioner, 
 
     v. 
 
Craig Boyson, D.C.,  
 
          Defendant-Appellant. 
 
FILED 
 
JUN 29, 2005 
 
Cornelia G. Clark 
Clerk of Supreme Court 
 
 
 
 
 
REVIEW of a decision of the Court of Appeals.  Affirmed.   
 
¶1 
JON P. WILCOX, J.   The plaintiff, Gary Hannemann 
(Hannemann), seeks review of a published court of appeals 
decision, Hannemann v. Boyson, 2004 WI App 96, ¶1, 273 
Wis. 2d 457, 681 N.W.2d 561, affirming in part, reversing in 
part, and remanding with directions a judgment of the Outagamie 
County Circuit Court, Harold V. Froehlich, Judge.  The circuit 
court entered judgment on the jury verdict in favor of Hannemann 
in his chiropractic malpractice case against the defendant, Dr. 
Craig Boyson (Boyson).  The court of appeals held, inter alia, 
that the special verdict submitted to the jury was erroneous 
No. 
2003AP1527   
 
2 
 
because it asked only whether Boyson was negligent in his 
treatment of Hannemann and did not separately ask whether Boyson 
failed to obtain Hannemann's informed consent for the procedure 
that allegedly caused his injury.  Id.1   
¶2 
We agree with Boyson and the court of appeals that 
negligent treatment and failure to obtain informed consent in 
the context of chiropractic malpractice are two different issues 
that require separate verdict questions.  We conclude that 
although the practice of chiropractic and the practice of 
medicine are distinct health care professions, the obligation of 
the practitioners of both to disclose the risks of the treatment 
and care they provide should be the same.  While the actual 
disclosures 
will 
inevitably 
vary 
between 
doctors 
and 
chiropractors, the nature of the duty and limitations thereon 
should be the same.  A patient of chiropractic has the same 
right as a patient of medical practice to be informed of the 
material risks of the proposed treatment or procedure so that he 
may make an informed decision whether to consent to the 
procedure or treatment.  As such, we hold that the scope of a 
chiropractor's duty to obtain informed consent is the same as 
that of a medical doctor.   
                                                 
1 The court of appeals rejected Boyson's other arguments 
that the circuit court erred by eliminating language from the 
standard informed consent jury instruction and by giving a 
standard causation instruction.  Hannemann v. Boyson, 2004 WI 
App 96, ¶1, 273 Wis. 2d 457, 681 N.W.2d 561.  Boyson did not 
file a cross appeal on these issues and we therefore do not 
address them.   
No. 
2003AP1527   
 
3 
 
¶3 
Furthermore, we conclude that the circuit court's 
failure to submit a separate special verdict on informed consent 
after separately instructing the jury on negligent treatment and 
informed consent constituted prejudicial error.  We therefore 
affirm the decision of the court of appeals reversing part of 
the judgment of the circuit court and remanding the case for a 
new trial.  
I. 
FACTUAL BACKGROUND 
¶4 
On August 21, 2000, Hannemann filed a complaint 
against Boyson in Outagamie County Circuit Court, alleging that  
"[f]rom August 7 through August 23, 1997, the defendant 
negligently provided chiropractic treatment to the plaintiff, 
Gary Hannemann, as a proximate consequence to which the 
plaintiff suffered serious and permanent injury . . . ."  As 
stated with more particularity in his scheduling conference 
statement, Hannemann alleged that "[t]he defendant negligently 
adjusted the plaintiff's cervical spine resulting in the 
plaintiff suffering a stroke with permanent disability."   
¶5 
A four-day jury trial was held beginning on August 15, 
2003.  During voir dire, Hannemann's attorney began arguing the 
theory that Boyson failed to provide informed consent by asking 
the potential jurors if they thought it was wrong for a doctor 
to warn a patient about the possibility of harm before 
performing a procedure, even if "it's a very remote risk" that 
may result in serious injury or death.  During opening 
statements, 
Hannemann's 
attorney 
concentrated 
on 
Boyson's 
alleged failure to discuss the risks inherent in performing a 
No. 
2003AP1527   
 
4 
 
cervical adjustment with Hannemann and his failure to perform 
appropriate tests on Hannemann.   
¶6 
The 
following 
facts 
and 
factual 
disputes 
were 
developed at trial.  Hannemann began seeing Boyson in July 1996 
due to lower back spasms and headaches he experienced as a 
result of his job, which required long periods of driving.  
Hannemann had previously undergone a spinal fusion operation.  
Boyson testified that Hannemann also complained of numbness and 
tingling in his arm.  Boyson stated that he took a patient 
history and performed various tests on Hannemann.  It is 
undisputed that Boyson did not perform a "George's Test," which 
is designed to test for neurovascular injuries, because he 
believed such a test was invalid.  However, Boyson testified 
that he performed several other tests that served the same 
purpose as the "George's Test."  He also stated that he 
performed x-rays on Hannemann.   
¶7 
Boyson diagnosed Hannemann with cervical subluxation 
dysfunction.  Boyson testified that when Hannemann began his 
treatment, he described the proposed treatment and discussed the 
various risks and benefits of chiropractic adjustment.  The 
record indicates that Hannemann signed informed consent forms on 
two occasions.2  However, it is undisputed that Boyson did not 
                                                 
2 The forms, dated July and November 1996, provide, in 
pertinent part: 
I the undersigned, a patient in this office, hereby 
authorize BOYSON CHIROPRACTIC OFFICE to administer 
such treatment as is necessary, and to perform the 
following therapy and manipulation and such additional 
No. 
2003AP1527   
 
5 
 
warn Hannemann that chiropractic treatment carried a risk of the 
patient suffering a stroke or other neurovascular injuries.  
Boyson explained that the reason he never discussed the risk of 
stroke was that to his recollection, at the time there was no 
definitive correlation between chiropractic adjustments and 
stroke and that "the risk of that is so astronomical that it 
wasn't a major factor."   
¶8 
Throughout 
the 
course 
of 
his 
treatment, 
Boyson 
performed adjustments on Hannemann's entire spine and neck in 
order to place it in proper alignment.  After a gap in his 
treatment, Hannemann saw Boyson in November 1996, following his 
involvement in an automobile accident.  In July 1997, Hannemann 
saw a medical doctor for headaches and neck stiffness and was 
diagnosed with a form of viral meningitis.   
¶9 
Following 
another 
two-month 
gap 
in 
chiropractic 
treatment, Hannemann returned again to see Boyson on August 7, 
1997, complaining of severe headaches.  Boyson testified that he 
took a brief patient history of Hannemann and performed a brief 
                                                                                                                                                             
therapy 
or 
procedures 
as 
are 
considered 
therapeutically necessary on the basis of findings 
during the course of said treatment. 
I hereby certify that I have read and fully understand 
the 
reasons 
above 
Authorization 
for 
Chiropractic 
Treatments, the reasons why the above named treatment 
is considered necessary, its advantage and possible 
complications, if any, as well as possible alternative 
modes of treatment, which were explained to me by 
BOYSON CHIROPRACTIC OFFICE. 
I also certify that no guarantee or assurance has been 
made as to the results that may be obtained.   
No. 
2003AP1527   
 
6 
 
exam.  Boyson testified that Hannemann did not inform him of his 
meningitis diagnosis during this visit.   
¶10 Hannemann again saw Boyson after a long day of driving 
on Thursday, August 21, 1997, complaining of lower back spasms 
and headaches.  Hannemann testified that Boyson administered an 
adjustment to his lower back and neck.  However, Hannemann 
stated that when Boyson adjusted his neck this time, he 
experienced a great deal of pain and heard a loud "crack."  
Hannemann stated that Boyson did not respond when he stated that 
he had experienced an unusual amount of pain after the 
adjustment. 
 
Boyson 
testified 
that 
the 
adjustment 
he 
administered on that date was no different than his previous 
adjustments.  Boyson also stated that he performed electrical 
muscle stimulation therapy on that date.  Boyson denied 
Hannemann ever told him the adjustment caused him pain.   
¶11 The next day, Hannemann began experiencing unusual 
symptoms that prompted him to call Boyson's office.  Hannemann 
testified that his leg was acting up and he was having 
difficulty walking.  Hannemann made an appointment to see Boyson 
the following day, even though Boyson's office was generally 
closed on Saturdays.   
¶12 Boyson testified that when Hannemann saw him on 
Saturday, August 23, Hannemann indicated he had developed 
numbness and tingling in his legs and under his foot, as well as 
a warm sensation in his thighs.  Boyson indicated that he had a 
discussion 
with 
Hannemann 
concerning 
his 
prior 
bout 
of 
meningitis at this point.  Boyson stated he checked Hannemann 
No. 
2003AP1527   
 
7 
 
for fixation and performed a series of tests that indicate 
whether a patient is suffering from meningitis.  Boyson stated 
all tests came back negative.   
¶13 Hannemann testified that Boyson asked him a series of 
questions, checked his reflexes, probed his body for pain, and 
then performed an adjustment to his neck.  Hannemann stated that 
this adjustment was similar to the one he received on Thursday, 
although he stated this one did not cause him pain.  Hannemann 
denied that Boyson advised him to go to the hospital or seek 
medical attention.   
¶14 Boyson denied that he performed an adjustment on 
Hannemann that Saturday and instead testified that he performed 
"a manual therapy technique[.]"  Boyson also stated that he 
recommended Hannemann see a medical doctor as soon as possible.   
¶15 Over the course of the day, Hannemann continued to 
experience a tingling feeling in his leg.  Hannemann went to bed 
that evening and awoke at 3:00 a.m. the next morning, unable to 
move one side of his body.  Hannemann also began experiencing 
urinary tract problems.  He was admitted to the emergency room 
and diagnosed with having suffered a stroke.   
¶16 Hannemann's standard of care expert witness, Dr. 
Kenneth 
Murkowski, 
testified 
that 
Boyson's 
treatment 
of 
Hannemann in August fell below the chiropractic standard of care 
because Boyson did not perform a series of diagnostic tests, 
including the "George's Test," which would indicate whether a 
patient was susceptible to neurovascular injury.  Boyson, in 
contrast, presented evidence from Dr. Jeffrey Wilder that the 
No. 
2003AP1527   
 
8 
 
general consensus in the chiropractic community was that the 
"George's Test" was invalid and that there is no way to screen a 
patient who may develop post-adjustment problems.  Wilder 
testified that Murkowski's opinions were based on an erroneous 
view of the facts and that Boyson's treatment of Hannemann on 
August 21 and 23 did not deviate from the standard of care.   
¶17 Murkowski also testified that Boyson was negligent in 
that he failed to obtain informed consent because Murkowksi 
could "find no informed consent in the records at all."  
Specifically, he stated that informed consent should include a 
warning to the patient that one of the risks of chiropractic 
treatment is neurovascular injury, including stroke.  Hannemann 
maintained that he would not have subjected himself to the 
adjustment had he known of the risk of stroke.  Wilder testified 
that Boyson did, in fact, obtain informed consent, and that the 
record reflected this was done on two occasions.  He stated that 
he had no clinical criticism of Boyson for failing to inform 
Hannemann about the possible risk of a stroke.  However, during 
cross-examination, Wilder admitted that most informed consent 
forms, including the ones he personally had used, disclosed the 
risk of neurovascular injury as a remote consequence of cervical 
adjustment.   
¶18 Hannemann also presented evidence that the very act of 
performing a cervical adjustment in the face of unexplained 
neurological symptoms constituted negligence.   
¶19 The parties disagreed as to whether the cervical 
adjustment Boyson allegedly administered on August 23, 1997, was 
No. 
2003AP1527   
 
9 
 
the cause of Hannemann's stroke, or whether the stroke was the 
result of complications from Hannemann's viral meningitis.  The 
parties also disputed whether there is a recognized link between 
stroke and cervical adjustments and, if so, the frequency with 
which 
stroke 
is 
connected 
to 
cervical 
adjustments. 
 
As 
Hannemann's expert testified, the statistics "are all over the 
place," and the reported instances of such occurrences ranged 
anywhere from one in a million to 55 out of 177.   
¶20 At the close of evidence, the parties disputed what 
instructions should be read to the jury.  Specifically, the 
parties disagreed as to whether the limitations on the informed 
consent 
obligations 
of 
medical 
doctors 
should 
apply 
to 
chiropractors and whether the jury should be instructed as to 
negligence 
and 
informed 
consent, 
or 
simply 
negligence.  
Hannemann argued that informed consent for chiropractic is 
simply part of the standard of care, whereas Boyson argued 
informed consent is a separate obligation that focuses on what a 
reasonable patient would want to know and is not dependent on 
the standards in the chiropractic community.   
¶21 The parties also disagreed as to the form of the 
special verdict.  Boyson argued that the questions on informed 
consent and negligence be submitted separately to the jury.  
Hannemann argued that the jury should be asked to answer only 
the question of negligence in treatment because informed consent 
is simply part of the standard of care.  The court decided to 
submit only the negligence verdict, stating:  "We are not going 
No. 
2003AP1527   
 
10 
 
to mess with the verdict.  Let the appellate court straighten 
this case out if it leads to it."   
¶22 During closing arguments when discussing liability, 
Hannemann's attorney again focused greatly on the fact that 
Boyson allegedly failed to obtain the proper informed consent.  
While he also argued that Boyson was negligent in failing to 
perform appropriate tests on Hannemann, namely, the "George's 
Test," his main argument was that Boyson was negligent because 
he failed to discuss the risks of neurovascular injury:   
What did the doctor not do? He didn't recognize 
the problem and he did not inform on that Saturday 
morning, he did not inform Gary Hannemann of the risk 
that he was about to confront with another adjustment.  
He did not tell him, Gary it’s a known fact that there 
is an association between cervical adjustment and 
people who have strokes.  He did not tell him you had 
developed very strange neurological symptoms that may 
indicate that you're in the process of having a 
neurovascular injury.  He did not tell him there are 
options, maybe you should go to a medical doctor, 
maybe we should do nothing.   
What he did is he decided to proceed with an 
adjustment, that is exactly what he did. . . . He 
didn't talk to Gary about the risks.  He didn’t do a 
complete neurological and orthopedic exam. . . . He 
didn't tell Gary to get medical help.   
¶23 Following 
closing 
arguments, 
the 
circuit 
court 
instructed the jury.  The court read a modified version of Wis 
JI——Civil 
1023.8, 
Professional 
Negligence: 
 
Chiropractor-
Treatment.  The court also read a modified version of Wis JI——
Civil 1023.2, governing medical informed consent.  The court 
instructed the jury: 
No. 
2003AP1527   
 
11 
 
A chiropractor has the duty to provide his 
patient with information necessary to enable the 
patient to make an informed decision about a procedure 
and alternative choices of treatments.  If the 
chiropractor fails to perform this duty, he is 
negligent.   
To meet this duty to inform his patient, the 
chiropractor 
must 
provide 
his 
patient 
with 
the 
information a reasonable person in the patient's 
position would regard as significant when deciding to 
accept or reject the medical treatment.  In answering 
this question, you should determine what a reasonable 
person in the patient's position would want to know in 
consenting to or rejecting a chiropractic treatment.  
However, the chiropractor's duty to inform does 
not require disclosure of: 
Information beyond what a reasonably, well-
qualified 
chiropractor 
in 
a 
similar 
classification would know; Extremely remote 
possibilities 
that 
might 
falsely 
or 
detrimentally alarm the patient.3   
                                                 
3 Wisconsin 
JI——Civil 
1023.2, 
Professional 
Negligence:  
Medical:  Informed Consent (2001), provides: 
Question _____ asks: 
Did (doctor) fail to disclose information about 
the (insert treatment or procedure) necessary for 
(patient) to make an informed decision? 
A doctor has a duty to provide (his)(her) patient 
with information necessary to enable the patient to 
make 
an 
informed 
decision 
about 
a 
(diagnostic)(treatment)(procedure) 
and 
alternative 
choices of (diagnostic)(treatments)(procedures).  If 
the doctor fails to perform this duty, (he)(she) is 
negligent.   
To meet this duty to inform (his)(her) patient, 
the doctor must provide (his)(her) patient with the 
information a reasonable person in the patient's 
position would regard as significant when deciding to 
accept 
or 
reject 
(a)(the) 
medical 
(diagnostic)(treatment)(procedure).  In answering this 
No. 
2003AP1527   
 
12 
 
                                                                                                                                                             
question, you should determine what a reasonable 
person in the patient's position would want to know in 
consenting 
to 
or 
rejecting 
a 
medical 
(diagnostic)(treatment)(procedure). 
The 
doctor must 
inform 
the 
patient 
whether 
(a)(the)(diagnostic)(treatment)(procedure) 
is 
ordinarily performed in the circumstances confronting 
the 
patient, 
whether 
alternate 
(treatments)(procedures) 
approved 
by 
the 
medical 
profession are available, what the outlook is for 
success 
or 
failure 
of 
each 
alternate 
(treatment)(procedure), and the benefits and risks 
inherent in each alternate (treatment)(procedure). 
However, the physician's duty to inform does not 
require disclosure of: 
[•Information 
beyond 
what 
a 
reasonably, 
well-qualified 
physician 
in 
a 
similar 
medical classification would know;] 
[•Detailed technical information that in all 
probability 
the 
patient 
would 
not 
understand;] 
[•Risks apparent or known to the patient;] 
[•Extremely remote possibilities that might 
falsely or detrimentally alarm the patient;] 
[•Information in emergencies where failure 
to provide treatment would be more harmful 
to the patient than treatment;] 
[•Information in cases where the patient is 
incapable of consenting.] 
 
[If (doctor) offers you an explanation as to why 
(he)(she) did not provide information to (plaintiff), 
and 
if 
this 
explanation 
satisfies 
you 
that 
a 
reasonable person in (plaintiff)'s position would not 
have wanted to know that information, then (doctor) 
was not negligent].   
No. 
2003AP1527   
 
13 
 
¶24 However, the court submitted only a negligence verdict 
to the jury, which asked, in pertinent part: 
Question 1:  Was Dr. Craig Boyson negligent with 
respect to his care and treatment of Gary Hannemann in 
August of 1997? 
 
 
 
 
Answer:  ____ 
Question 2:  If you answered question 1 above "yes," 
please answer the following question.  Was the 
negligence of Dr. Craig Boyson a cause of Gary 
Hannemann's neurovascular injury?   
 
 
 
 
Answer:  ____ 
Question 3:  Was Gary Hannemann negligent with respect 
to his own care by failing to follow the instructions 
of his treating physicians? 
 
 
 
 
Answer:  ____ 
Question 4:  If you answered question 3 above "yes," 
please answer the following question.  Was the 
negligence 
of 
Gary 
Hannemann 
a 
cause 
of 
his 
neurovascular injury? 
 
 
 
 
Answer:  ____ 
¶25 The court did not submit a special verdict question on 
informed consent.4  The jury answered questions one through three 
                                                 
4 Wis JI——Civil 1023.1 Professional Negligence:  Medical:  
Informed Consent:  Special Verdict (2001), provides: 
Questions 1, 2, and 3 of the special verdict form 
relate to the issue of informed consent and read as 
follows: 
Question 1: 
Did 
(doctor) 
fail 
to 
disclose 
information about the (insert treatment 
or procedure) necessary for (patient) 
to make an informed decision? 
 
 
 
 
Answer: 
 
__________________ 
No. 
2003AP1527   
 
14 
 
"yes" and answered "no" to question four.  The jury awarded 
Hannemann $227,000 in damages.   
II. PROCEDURAL POSTURE 
¶26 On March 10, 2003, Boyson filed a motion for a new 
trial, arguing, inter alia, that the circuit court erred in 
failing to include special verdict questions on informed consent 
consistent with Wis JI——Civil 1023.1.  By order dated May 2, 
2003, the circuit court denied the motion for a new trial.  On 
that same day, the circuit court entered judgment on the 
verdict.   
¶27 Boyson appealed the judgment, and the court of appeals 
reversed in part, concluding that "failure to obtain informed 
                                                                                                                                                             
 
 
 
 
 
 
 
 
Yes or No 
Question 2: 
If you answered question 1 "yes," then 
answer this question:  If a reasonable 
person, placed in (patient)'s position, 
had been provided necessary information 
about 
the 
(insert 
treatment 
or 
procedure), 
would 
that 
person 
have 
(refused)(accepted) 
the 
(insert 
treatment or procedure)?   
 
 
 
 
Answer: 
 
__________________ 
 
 
 
 
 
 
 
 
Yes or No 
Question 3: 
If you have answered both questions 1 
and 2 "yes," then answer this question:  
Was the failure by (doctor) to disclose 
necessary 
information 
about 
(insert 
treatment or procedure) a cause of 
injury to (patient)?  
 
 
 
 
Answer: 
 
__________________ 
 
 
 
 
 
 
 
 
Yes or No 
No. 
2003AP1527   
 
15 
 
consent and negligent treatment are two different issues that 
require 
different 
verdict 
questions." 
 
Hannemann, 
273 
Wis. 2d 457, ¶1.  The court of appeals reasoned that while Wis 
JI——Civil 1023.1 is based on a statute governing medical 
informed consent, Wis. Stat. § 448.30 (2003-04),5 "the legal 
theories of informed consent for medical doctors and for 
chiropractors are the same."  Id., ¶20.  The court of appeals 
stated that both theories are based on the patient's right to 
self-determination, including the right to refuse treatment.  
Id., ¶19.   
¶28 In addition, the court of appeals found it significant 
that both medical doctors and chiropractors are health care 
providers and both are licensed by state examining boards.  Id., 
¶21.  Further, the court of appeals noted that while Murphy v. 
Nordhagen, 222 Wis. 2d 574, 584, 588 N.W.2d 96 (Ct. App. 1998), 
stated that informed consent did not apply to chiropractors,6 the 
Chiropractic Examining Board created Wis. Admin. Code § Chir 
                                                 
5 All references to the Wisconsin Statutes are to the 2003-
04 version unless otherwise noted.   
6 Neither party contends that the concept of informed 
consent is wholly inapplicable to chiropractors.   
No. 
2003AP1527   
 
16 
 
11.02(5)(May, 1997),7 which contains an explicit requirement that 
chiropractors 
keep 
records 
of 
patients' informed consent.  
Hannemann, 273 Wis. 2d 457, ¶19.  Therefore, it held that Wis 
JI——Civil 1023.1 "is a model for chiropractic negligence as well 
as medical informed consent."  Id., ¶21.   
¶29 Further, the court of appeals noted that a special 
verdict must cover all material issues of ultimate fact and that 
here, the jury was not asked to determine whether the three 
elements of failure to obtain informed consent were present.  
The court therefore ruled that "the verdict questions did not 
cover the material issues of ultimate fact necessary to prove 
Boyson failed to obtain Hannemann's informed consent."  Id., 
¶22.  Finally, the court concluded that the circuit court's 
error in failing to submit a separate verdict on informed 
consent was not harmless:  "[W]e do not know whether the jury 
found Boyson guilty of negligent treatment or failure to obtain 
informed consent.  Thus, we conclude it is reasonably possible 
the error affected the jury's determination."  Id., ¶24.   
 
 
                                                 
7 Wisconsin Admin. Code § Chir 11.02(5) appeared in the 
administrative register in May 1997 and was effective June 1, 
1997.  This provision has not changed since it was first 
promulgated.  See Wis. Admin. Code § Chir 11.02(5)(July, 2004).  
Therefore, all references to the administrative code are to the 
May 1997 version unless otherwise indicated.  It is noteworthy 
that 
the 
court of appeals 
in Murphy 
v. 
Nordhagen, 222 
Wis. 2d 574, 584, 588 N.W.2d 96 (Ct. App. 1998), did not mention 
this administrative code provision in its brief discussion of 
informed consent.   
No. 
2003AP1527   
 
17 
 
III. ISSUE 
¶30 The precise issue on appeal is whether the circuit 
court erred in failing to submit a special verdict on informed 
consent.8  The form of the special verdict is within the circuit 
court's discretion, so long as it covers all material issues of 
fact.  Meurer v. ITT Gen. Controls, 90 Wis. 2d 438, 445-46, 280 
N.W.2d 156 (1979).  In the present case, the circuit court 
submitted 
the 
special 
verdict 
on 
negligent 
chiropractic 
treatment.  It did not submit a separate special verdict on the 
issue of informed consent, although it instructed the jury on 
informed consent.  Whether the circuit court erred in failing to 
submit 
special 
verdict 
questions 
on 
informed 
consent 
is 
dependent upon the scope of a chiropractor's duty of informed 
consent and whether all material issues of ultimate fact 
pertinent thereto were covered under the negligent treatment 
special verdict.  The scope of a legal duty is a question of 
law.  Wiegert v. Goldberg, 2004 WI App 28, ¶12, 269 Wis. 2d 695, 
676 N.W.2d 522.   
IV. ANALYSIS 
A. 
Scope of Chiropractic Informed Consent 
¶31 The issue in this case concerns the scope of a 
chiropractor's duty to obtain informed consent from his patient 
before proceeding with treatment and whether such duty is 
similar to a medical doctor's duty to obtain informed consent.  
                                                 
8 We emphasize that we do not address the issue of informed 
consent for health care providers not discussed in this opinion.   
No. 
2003AP1527   
 
18 
 
Boyson argues that a chiropractor's duty to obtain informed 
consent is subject to the same parameters and limitations as 
that of a physician and that a failure to obtain informed 
consent constitutes a separate basis for finding a chiropractor 
liable in a malpractice action.  Hannemann contends that 
chiropractic informed consent is not governed by the same 
standards as informed consent in the medical context.  Hannemann 
asserts that a chiropractor's informed consent obligations are 
limited to the standard form patients sign before beginning 
treatment. 
 
According 
to 
Hannemann, 
informed 
consent 
in 
chiropractic is not a separate basis upon which a chiropractor 
can be found liable in a malpractice action; rather, it is 
simply part of the chiropractic standard of care.  For the 
foregoing reasons, we agree with Boyson.  
¶32 In Murphy, 222 Wis. 2d at 584-85, the court of 
appeals, with very little analysis, determined that the law of 
informed consent was "facially inapplicable to a chiropractic 
negligence case."  Murphy reasoned that the law of informed 
consent was based on § 448.30, whose explicit language applies 
only to physicians.  Id.  Neither party in the present dispute 
argues that the law of informed consent is entirely inapplicable 
to the practice of chiropractic.   
¶33 A year before Murphy was decided, the Chiropractic 
Examining Board promulgated Wis. Admin. Code § Chir 11.02, 
entitled "Patient record contents."  Wisconsin Admin. Code 
§ Chir 11.02(5) provides:  "Patient records shall include 
documentation of informed consent of the patient, or the parent 
No. 
2003AP1527   
 
19 
 
or guardian of any patient under the age of 18, for examination, 
diagnostic testing and treatment."  The code provision was made 
effective June 1997.  Therefore, there is no dispute that a 
chiropractor has an obligation to obtain informed consent; 
rather, the question is what that duty entails.  As the 
administrative code does not describe the obligation to secure 
informed consent or set forth any parameters or limitations on 
the obligation, we examine the concept of informed consent under 
our common law.   
¶34 The 
concept 
of 
informed 
consent 
in 
this 
state 
originated in context of medical malpractice.  A physician's 
failure to obtain a patient's permission for a non-emergency 
procedure was considered an assault and battery, in that it 
constituted an unwanted touching of another person.  Trogun v. 
Fruchtman, 58 Wis. 2d 569, 596, 598, 207 N.W.2d 297 (1973).  The 
obligation to secure informed consent before performing a 
procedure was premised on the notion that "a person of sound 
mind has a right to determine, even as against his physician, 
what is to be done to his body."  Id. at 596.   
¶35 In Trogun, this court determined that it was no longer 
appropriate to treat the failure to obtain informed consent as 
an assault and battery and instead "recognize[d] a legal duty, 
bottomed upon a negligence theory of liability, in cases wherein 
it is alleged the patient-plaintiff was not informed adequately 
of the ramifications of a course of treatment."  Id. at 600.  
However, even under this negligence-based theory, a physician's 
obligation to disclose risks and obtain consent is determined in 
No. 
2003AP1527   
 
20 
 
light of what a reasonable patient would want to know when 
making 
a 
medical 
decision 
rather 
than 
the 
standard 
for 
disclosure in the relevant community.  Id. at 601-04.  In other 
words, even under the negligence theory of informed consent, 
"'the patient's right of self-decision is the measure of the 
physician's duty to reveal.'"  Id. at 602 (quoting Cobbs v. 
Grant, 502 P.2d 1, 11 (Cal. 1972))(emphasis added).  
¶36 Therefore, applying the Trogun theory of informed 
consent, this court has held: 
[A] physician has a duty to make a reasonable 
disclosure to his patient of the significant risks in 
view of the gravity of the patient's condition, the 
probabilities 
of 
success, 
and 
any 
alternative 
treatment 
or 
procedures 
if 
such 
are 
reasonably 
appropriate so that the patient has the information 
reasonably 
necessary 
to 
form 
the 
basis 
of 
an 
intelligent and informed consent to the proposed 
treatment or procedure. 
Scaria v. St. Paul Fire & Marine Ins. Co., 68 Wis. 2d 1, 11, 227 
N.W.2d 647 (1975).  The duty is not measured by the standards 
used in the relevant medical community because:   
The right to be recognized and protected is the right 
of the patient to consent or not to consent to a 
proposed medical treatment or procedure.  Because of 
the patient's lack of professional knowledge, he 
cannot make a rational reasonable judgment unless he 
has been reasonably informed by the doctor of the 
inherent and potential risks.  The right of the 
patient and the duty of the doctor are standards 
recognized and circumscribed by the law and are not 
entirely dependent upon the customs of the profession.  
Id. at 12.   
¶37 As 
the 
duty 
to 
disclose 
the 
risks 
of 
medical 
procedures and treatment arises from the patient's right to make 
No. 
2003AP1527   
 
21 
 
an informed decision and refuse the bodily intrusion accompanied 
by the procedure or treatment, there are limits to what a doctor 
must disclose: 
A doctor should not be required to give a detailed 
technical medical explanation that in all probability 
the patient would not understand.  He should not be 
required to discuss risks that are apparent or known 
to the patient.  Nor should he be required to disclose 
extremely remote possibilities that at least in some 
instances might only serve to falsely or detrimentally 
alarm the particular patient.  Likewise, a doctor's 
duty to inform is further limited in cases of 
emergency or where the patient is a child, mentally 
incompetent or a person is emotionally distraught or 
susceptible to unreasonable fears.   
Id. at 12-13.   
¶38 Moreover, a doctor's duty to disclose the risks of 
treatments or procedures is limited to those risks that a 
reasonable person would want to know.  Id. at 15.  Thus, it is 
not sufficient for a patient to demonstrate that in hindsight he 
would not have undergone the procedure if he had been appraised 
of the risks; rather, there must be proof that a reasonable 
person, when appraised of the risks involved, would not have 
consented to the procedure in question.  Id.    
¶39 In essence, a doctor must "make such disclosures as 
appear reasonably necessary under circumstances then existing to 
enable 
a 
reasonable 
person 
under 
the 
same 
or 
similar 
circumstances confronting the patient at the time of disclosure 
to intelligently exercise his right to consent or to refuse the 
treatment or procedure proposed."  Id. at 13.  In other words,  
A physician who proposes to treat a patient or 
attempt to diagnose a medical problem must make such 
No. 
2003AP1527   
 
22 
 
disclosures as will enable a reasonable person under 
the circumstances confronting the patient to exercise 
the patient's right to consent to, or refuse the 
procedure 
proposed or 
to 
request 
an 
alternative 
treatment or method of diagnosis.  
Martin v. Richards, 192 Wis. 2d 156, 176, 531 N.W.2d 70 (1995).  
However, obtaining informed consent is not necessarily a one-
time occurrence:  "a substantial change in circumstances, be it 
medical or legal, requires a new informed consent discussion."  
Fischer v. Wis. Patients Comp. Fund, 2002 WI App 192, ¶17, 256 
Wis. 2d 848, 650 N.W.2d 75 (citing Schreiber v. Physicians Ins. 
Co., 223 Wis. 2d 417, 437, 588 N.W.2d 26 (1999)). 
¶40 Although liability for failure to obtain informed 
consent is premised on negligence principles, it is nonetheless 
treated under the law as a separate and distinct form of 
malpractice:  "A failure to diagnose is one form of medical 
malpractice.  A failure to obtain informed consent is another 
discrete form of malpractice, requiring a consideration of 
additional and different factors."  Finley v. Culligan, 201 
Wis. 2d 611, 628, 548 N.W.2d 854 (Ct. App. 1996) (citing Knief 
v. Sargent, 40 Wis. 2d 4, 8, 161 N.W.2d 232 (1968)); Wis JI——
Civil 1023).  "[T]he touchstone of the test [for informed 
consent] [i]s what the reasonable person in the position of the 
patient would want to know."  Schreiber, 223 Wis. 2d at 427.   
¶41 We see no reason why these principles of informed 
consent, while initially developed and applied in the context of 
medical 
malpractice, 
are 
not 
equally 
applicable 
to 
chiropractors.  Hannemann's main argument against applying the 
above principles of informed consent is that chiropractors are 
No. 
2003AP1527   
 
23 
 
not medical doctors, do not practice medicine, and are not 
subject to the same standard of care as physicians.  Hannemann 
is correct that there are obvious differences between the 
practice of chiropractic and the practice of medicine.      
[T]he legislature has recognized the practice of 
chiropractic as a separate and distinct health care 
discipline. . . .   [B]y limiting chiropractors to the 
use of chiropractic adjustments and the principles or 
techniques of chiropractic science in the diagnosis, 
treatment or prevention of disease while prohibiting 
the use of traditional medical tools, e.g., drugs or 
surgery, the legislature has recognized that the 
practice of chiropractic is distinct from the practice 
of medicine.   
Kerkman v. Hintz, 142 Wis. 2d 404, 415-16, 418 N.W.2d 795 
(1988).  More specifically,  
[A] chiropractor does not treat or diagnose disease.  
Instead, a chiropractor's practice is limited to the 
analysis 
and 
correction 
of 
subluxation. 
 
The 
chiropractor's function is to locate the subluxation, 
if it exists, adjust it back to the correct position, 
and then allow the body to restore itself to normalcy.  
A medical doctor's practice, on the other hand, is 
completely opposite.  The medical doctor is concerned 
with the diagnosis and treatment of the diseased area 
through the use of drugs and surgery or other 
techniques.   
Id. at 416.   
¶42 However, "[i]n licensing chiropractors to examine into 
the cause of departure from complete health and by authorizing 
chiropractors to diagnose, treat or prevent disease, the 
legislature has recognized chiropractors as providers of health 
care."  Id. at 415-16.  Furthermore, our courts have determined 
that 
chiropractors 
are 
"health 
care 
providers" 
under 
Wis. Stat. § 893.55, which sets forth the limitation period for 
No. 
2003AP1527   
 
24 
 
medical malpractice claims against health care providers.  Arenz 
v. Bronston, 224 Wis. 2d 507, 515, 592 N.W.2d 295 (Ct. App. 
1999).  Thus, while the practice of chiropractic is separate and 
distinct from that of medicine, it is nonetheless a "health care 
discipline."  Kerkman, 142 Wis. 2d at 415-16.  In Arenz, the 
court of appeals reasoned that chiropractors met the statutory 
definition of "health care provider" because, like medical 
doctors, "[t]hey are involved in the diagnosis, treatment or 
care of their patients, and they are licensed by a state 
examining board."  Arenz, 224 Wis. 2d at 515.   
¶43 As discussed supra, the concept of informed consent 
developed out of the right of every person to refuse unwanted 
medical treatment and control what is done to his body.  "The 
doctrine of informed consent comes from the common law and stems 
from the fundamental notion of the right to bodily integrity[.]"  
Martin, 192 Wis. 2d at 169.  These principles continue to form 
the basis of the modern concept of informed consent.  Trogun, 58 
Wis. 2d at 602.  Thus, the right to informed consent arises not 
from anything peculiar to the medical profession, but from the 
"notion that an adult has a 'right to determine what shall be 
done with his own body . . . .'"  Schreiber, 223 Wis. 2d at 426 
(quoting Schloendorff v. Soc'y of New York Hosp., 105 N.E. 92, 
93 (N.Y. 1914), overruled on other grounds by Bing v. Thunig, 
143 N.E.2d 3 (N.Y. 1957)).  
¶44 Medical doctors are obligated to disclose and discuss 
the material risks of any given procedure or treatment with 
their patients so that their patients may make informed 
No. 
2003AP1527   
 
25 
 
decisions as to whether they want to consent to bodily 
intrusions and proceed with the recommended procedure or 
treatment.  Chiropractors, like medical doctors, are health care 
professionals involved in the application of procedures and 
treatments to the human body.  We see no reason why the scope of 
an individual's right to be informed of the risks inherent in 
bodily intrusions via chiropractic treatment and procedures 
should be any different from his right to be informed of the 
risks inherent in bodily intrusions via medical treatment and 
procedures.   
¶45 While the two disciplines are distinct forms of health 
care, there is no logical reason why a patient of chiropractic 
should not have the same right as a patient of medical practice 
to be informed of the risks material to proposed treatments or 
procedures so as to be able to make an informed decision and 
consent to the proposed treatments or procedures.  In other 
words, while the specific treatments and procedures utilized in 
the practice of chiropractic and the practice of medicine may 
differ, there is no reason why the practitioners of these 
disciplines should not have the same obligation to disclose the 
material risks of the procedures and treatments they utilize.   
¶46 We 
reject 
Hannemann's 
repeated 
assertions 
that 
informed consent in chiropractic is merely a one-time obligation 
that is satisfied by simply providing a form before beginning 
treatment.  The form may be evidence or documentation of the 
risks disclosed to a patient, but the form itself is not 
informed 
consent. 
 
Informed 
consent 
is 
"mak[ing] 
such 
No. 
2003AP1527   
 
26 
 
disclosures as will enable a reasonable person under the 
circumstances confronting the patient to exercise the patient's 
right to consent to, or to refuse the procedure proposed or to 
request an alternative treatment or method of diagnosis."  
Martin, 192 Wis. 2d at 176.  In other words, informed consent is 
a duty to "make such disclosures as appear reasonably necessary 
under circumstances then existing to enable a reasonable person 
under the same or similar circumstances confronting the patient 
at the time of disclosure to intelligently exercise his right to 
consent or to refuse the treatment or procedure proposed."  
Scaria, 68 Wis. 2d at 13.   
¶47 Although 
the 
specifics 
of 
the 
disclosures 
will 
undoubtedly vary between the practice of medicine and the 
practice of chiropractic, the rules governing the scope and 
limits of the duty to disclose and obtain informed consent 
should be the same.  The scope and limits of the duty to 
disclose material risks and obtain informed consent are aptly 
set forth in Wis JI——Civil 1023.1.  While this instruction may 
need to be modified when applied to chiropractors, this can 
easily be accomplished. 
¶48 Hannemann's last argument is that Wis JI——Civil 1023.1 
should not apply to chiropractors because the jury instruction 
is based on § 448.30, which applies only to physicians.  Section 
448.30 
requires 
physicians 
to 
make 
certain 
disclosures 
pertaining to all viable modes of treatment.  Schreiber, 223 
Wis. 2d at 428.  Section 448.30 first became effective in 1982.  
See § 2, ch. 375, Laws of 1981.  In contrast, Wis JI——Civil 
No. 
2003AP1527   
 
27 
 
1023.1 was first adopted following this court's decisions in 
Trogun and Scaria in 1975.  See Law Note, Wis JI——Civil 1023.1.  
Moreover, § 448.30 was enacted in order to codify the common-law 
standards for informed consent set forth in Scaria.  See 
Schreiber, 223 Wis. 2d at 427-28; Law Note, Wis JI——Civil 
1023.1.  Furthermore, the scope and limitations on the duty of 
informed consent in Wis JI——Civil 1023.1 all derive from Trogun 
and its progeny, which adopted the reasonable patient standard 
for informed consent.  See Martin, 192 Wis. 2d at 176; Scaria, 
68 Wis. 2d at 13; Trogun, 58 Wis. 2d at 601-04.  Therefore, a 
physician's duty to obtain informed consent, while codified in 
§ 448.30, is not dependent on that statute for its existence.  
While our common-law informed consent jurisprudence has been 
codified with respect to one health care profession, we are not 
prohibited from extending that common law to another health care 
profession.   
¶49 In sum, we conclude that a chiropractor's duty of 
informed consent is to "make such disclosures as will enable a 
reasonable 
person 
under 
the 
circumstances 
confronting the 
patient to exercise the patient's right to consent to, or to 
refuse the procedure proposed or to request an alternative 
treatment or method of diagnosis."  Martin, 192 Wis. 2d at 176.  
He must "make such disclosures as appear reasonably necessary 
under circumstances then existing to enable a reasonable person 
under the same or similar circumstances confronting the patient 
at the time of disclosure to intelligently exercise his right to 
No. 
2003AP1527   
 
28 
 
consent or to refuse the treatment or procedure proposed."  
Scaria, 68 Wis. 2d at 13.   
B. 
Special Verdict Question 
 
¶50 Having determined that the scope of a chiropractor's 
duty to obtain informed consent is the same as that of a medical 
doctor, we next address whether the circuit court erred in 
failing to submit special verdict questions on informed consent.  
A special verdict must cover all material issues of ultimate 
fact.  Wis. Stat. § (Rule) 805.12(1).  The material issues of 
ultimate fact for a failure to provide informed consent are as 
follows:  (1) the patient was not informed of the risks in the 
proposed treatment or procedure of which a reasonable person in 
the patient's position would wish to be made aware; (2) a 
reasonable person in the patient's position presented with such 
information would not have chosen to submit to the treatment or 
procedure; and (3) the failure to disclose such information was 
a cause of the patient's injuries.  Martin, 192 Wis. 2d at 176, 
182-83; Scaria, 68 Wis. 2d at 13-17; Wis JI——Civil 1023.1.   
¶51 Here, the jury was not asked to find these ultimate 
issues of fact.  Rather, the jury was asked only whether Boyson 
was negligent in treating Hannemann and whether such negligent 
treatment was the cause of Hannemann's injuries.  The jury 
simply was not asked to find the three material issues of 
ultimate fact for failure to provide informed consent.   
¶52 We note that generally "[w]here a party might be found 
negligent in several respects a single question as to that 
party's negligence is permissible."  Meurer, 90 Wis. 2d at 446.  
No. 
2003AP1527   
 
29 
 
However, a failure to provide informed consent is a form of 
malpractice separate and discrete from negligence in treatment:  
"A failure to diagnose is one form of medical malpractice.  A 
failure to obtain informed consent is another discrete form of 
malpractice, 
requiring 
a 
consideration 
of 
additional 
and 
different factors."  Finley, 201 Wis. 2d at 628 (emphasis 
added).   
¶53 While the modern concept of informed consent is based 
on negligence principles, providing negligent treatment and 
failing to provide informed consent involve the violation of two 
separate duties and "the standards by which these duties must be 
measured are somewhat different[.]"  Scaria, 68 Wis. 2d at 20.  
As previously discussed, the duty to provide reasonable care in 
treatment is defined by the standards in the chiropractic 
community, whereas the duty to obtain informed consent is 
defined by what information a reasonable patient would want to 
know.   
¶54 Thus, this court has held that upon a proper motion 
the question of failure to provide informed consent should be 
stated separately from the question of negligent treatment.  Id.  
The court of appeals has held that a claim of informed consent 
is a separate cause of action that requires amendment of the 
pleadings or the implied consent of the parties to try the issue 
when the plaintiff pleads only negligence in treatment.  Finley, 
201 Wis. 2d at 629.  In Martin, 192 Wis. 2d at 182-83, this 
No. 
2003AP1527   
 
30 
 
court all but stated that an informed consent verdict that omits 
a cause question is fatally defective.9    
¶55 Here, the verdict not only omitted the cause question 
on informed consent, it omitted the first two questions as well.  
Thus, the jury was never asked whether the risk of stroke was 
information that a reasonable patient would want to know in 
deciding whether to submit to chiropractic treatment.  The jury 
was never asked whether a reasonable patient in Hannemann's 
position would have submitted to chiropractic treatment if 
presented with such information.  Finally, the jury was never 
asked whether the failure to inform Hannemann of the risk of a 
stroke was the cause of his injuries.   
¶56 In 
sum, 
the 
verdict 
submitted, 
negligence 
in 
chiropractic treatment, did not cover the material issues of 
ultimate 
fact 
for 
informed 
consent. 
 
The 
circuit 
court 
erroneously proceeded on the theory that failure to provide 
informed 
consent 
constituted 
negligence 
in 
chiropractic 
treatment and not a separate basis for liability.  Therefore, we 
conclude that the circuit court erroneously exercised its 
discretion in failing to submit a separate special verdict on 
informed consent.   
                                                 
9 The verdict in Martin v. Richards, 192 Wis. 2d 156, 182-
83, 531 N.W.2d 70 (1995), which omitted the cause question, was 
upheld only because the court determined that the parties waived 
the issue.   Indeed, the jury instruction on informed consent 
was revised following Martin because the committee believed that 
"the supreme court inferred it would have found a fatal defect 
had it not been for its conclusion the parties waived such a 
causation question."  Law Note, Wis JI——Civil 1023.1.   
No. 
2003AP1527   
 
31 
 
C. 
Harmless Error 
¶57 Having 
determined 
the 
circuit 
court 
erroneously 
exercised its discretion in failing to submit a separate special 
verdict on informed consent, we now address whether that error 
merits reversal.  An error does not require reversal unless it 
affects the substantial rights of the party seeking to set aside 
the judgment.  Wis. Stat. § (Rule) 805.18(2).  Thus, we must 
determine whether the error was prejudicial or harmless.  Town 
of Geneva v. Tills, 129 Wis. 2d 167, 184-85, 384 N.W.2d 701 
(1986).  The test for harmless error in civil cases is the same 
as that in criminal cases.  Id.   
To assess whether an error is harmless, we focus 
on the effect of the error on the jury's verdict.  
State v. Harvey, 2002 WI 93, ¶44, 254 Wis. 2d 442, 647 
N.W.2d 189. . . . This test is "'whether it appears 
"beyond a reasonable doubt that the error complained 
of did not contribute to the verdict obtained."'"  
Harvey, 254 Wis. 2d 442, ¶44 (quoting Neder v. United 
States, 527 U.S. 1, 15-16 (1999) quoting in turn 
Chapman v. California, 386 U.S. 18, 24 (1967)).  We 
have held that "in order to conclude that an error 
'did not contribute to the verdict' within the meaning 
of Chapman, a court must be able to conclude 'beyond a 
reasonable doubt that a rational jury would have 
[reached the same result] absent the error.'"  Id., 
¶48 n.14 (quoting Neder, 527 U.S. at 18).  In other 
words, if it is "clear beyond a reasonable doubt that 
a rational jury would have [rendered the same verdict] 
absent the error," then the error did not "'contribute 
to the verdict.'"  Neder, 527 U.S. at 15, 18 (citation 
omitted).   
State v. Weed, 2003 WI 85, ¶29, 263 Wis. 2d 434, 666 N.W.2d 485 
(alternations added).   
¶58 Here, the jury returned a verdict finding that Boyson 
was negligent with respect to his treatment of Hannemann.  
No. 
2003AP1527   
 
32 
 
Hannemann argues that even if the circuit court erred in failing 
to submit a separate special verdict on informed consent, such 
error was harmless because there was sufficient evidence to 
support the jury's verdict on negligent treatment.  We reject 
Hannemann's argument that the error was not harmless for several 
reasons.  First, the test for harmless error is not "a 
sufficiency of the evidence standard."  Id., ¶28.  The question 
is whether it is clear beyond a reasonable doubt that a rational 
jury would have found Hannemann liable for negligent treatment 
(the verdict actually rendered) had the circuit court properly 
submitted a separate special verdict on informed consent, such 
that it can be said beyond a reasonable doubt that the error did 
not contribute to the verdict obtained.   
¶59 From the beginning of trial, Hannemann focused heavily 
on Boyson's alleged failure to disclose the risk of stroke and 
obtain informed consent as a basis for finding that Boyson's 
treatment of Hannemann was negligent.  During voir dire, 
Hannemann repeatedly questioned jurors as to whether they 
thought it was "wrong" to expect a doctor to inform a patient as 
to the risks of a procedure and involve them in the process.10  
                                                 
10 The following exchange took place between Hannemann's 
attorney and the jury panel:   
Mr. Peterson:  When a doctor's procedure that 
he's going to employ in the treatment of a patient 
involves some inherent risk of harm, that the patient 
could be harmed by that procedure, do you think it's 
wrong to expect the doctor to talk to the patient to 
explain what the possibility of the harm is and 
No. 
2003AP1527   
 
33 
 
During opening statements, Hannemann again concentrated on 
Boyson's failure to obtain proper informed consent.  When 
discussing Hannemann's visit to Boyson on Saturday, August 23, 
Hannemann stated: 
Doctor Boyson was confused, concerned, and Dr. 
Boyson decided to do another adjustment, another what 
he calls chiropractic manual therapy.  And he did what 
Gary will tell you——and what I think by the end of the 
trial you will agree——was the same adjustment that he 
always did, the same kind of adjustment as he always 
did.  He didn’t say to Gary this time, just like he 
didn’t say any other time, Gary, I'm going to do an 
adjustment on your neck.  And what he didn't do this 
time is, he didn’t say, Gary, I'm going to do an 
adjustment on your neck despite the fact that you are 
                                                                                                                                                             
involve the patient in the decision as to whether he 
should go ahead with that? 
(No response) 
Mr. Peterson:  How about if the risk is a risk 
that's very rare; that it's a very remote risk; you 
know, it's very rare that this bad consequence, this 
bad thing that can happen actually does?  I assume 
that everyone would think that the more rare and the 
more remote it is, the less important it would be to 
talk to the patient about that.  Is there anyone who 
disagrees with that proposition? 
(No response) 
Mr. Peterson:  How about this?  How about if it's 
rare and remote, but what the consequence is, that you 
can be paralyzed or you can be killed as a consequence 
of what the doctor proposes to do?  Even if its rare, 
is there anyone here that doesn't think that the 
patient should be consulted and told about that so 
that they can make a decision?  They can participate 
in the decision as to whether whatever the problem is 
serious enough for them to confront being paralyzed, 
being killed?  Anybody disagree with that? 
(No response) 
No. 
2003AP1527   
 
34 
 
exhibiting 
symptoms 
of 
having 
some 
serious 
neurological deficits.  He didn’t tell him that he was 
at peculiar risk, very high risk.  He didn’t tell him, 
these symptoms might go away if I don't adjust you.  
And he went ahead with the adjustment anyhow with Gary 
in the complete dark.   
¶60 During 
trial, 
the 
parties 
presented 
conflicting 
evidence and disputed:  1) the cause of Hannemann's stroke; 2) 
whether Boyson actually performed an adjustment on August 23; 3) 
whether it was normal for chiropractors to warn of the risk of 
stroke; 4) whether the risk of stroke was extremely high or 
extremely low; 5) whether it is standard practice to perform a 
"George's Test" prior to an adjustment; 6) whether chiropractors 
can adequately test for susceptibility to neurovascular injury; 
and 7) whether Boyson informed Hannemann that he should see a 
medical doctor.   
¶61 Both parties agreed that Boyson did not perform a 
"George's Test" on August 23, although Boyson stated he 
performed other tests that produced results similar to the 
"George's Test."  Further, both parties agreed that at no point 
did Boyson warn Hannemann of the risk of neurovascular injuries, 
particularly stroke.  Hannemann presented evidence that Boyson 
was negligent in that he should not have performed the alleged 
August 23 adjustment at all in light of the symptoms Hannemann 
was presenting.   
¶62 More importantly, Hannemann's expert, Dr. Murkowski, 
opined that Boyson provided negligent treatment because he 
failed to obtain the proper informed consent.  Some of the most 
powerful evidence came during the cross-examination of Boyson's 
No. 
2003AP1527   
 
35 
 
expert, Dr. Wilder.  Although Dr. Wilder testified on direct 
that he had no clinical criticism of Boyson's failure to 
disclose the risk of neurovascular injuries, he admitted on 
cross-examination that almost all chiropractic colleges utilized 
informed consent forms that disclosed that neurovascular injury 
was a remote risk of cervical adjustment.  Dr. Wilder even 
admitted that the form he uses discloses such a risk.  Thus, 
while 
Hannemann's 
evidence 
on 
negligent 
treatment 
was 
contradicted, his evidence on informed consent was compelling.   
¶63 At the close of evidence, the circuit court separately 
instructed the jury on professional negligence in chiropractic 
treatment and informed consent.  The court read a modified 
version 
of 
Wis 
JI——Civil 
1023.8 
Professional 
Negligence:  
Chiropractor-Treatment.  The court also read a modified version 
of Wis JI——Civil 1023.2, governing medical informed consent. 
¶64 During 
closing 
arguments, 
Hannemann 
argued 
that 
Boyson's treatment fell below the chiropractic standard of care 
because Boyson failed to perform the appropriate tests on 
Hannemann before administering the adjustment and because Boyson 
failed to disclose the risk of a stroke and thus failed to 
obtain proper informed consent.11  However, by far, Hannemann's 
most extensive and emphatic arguments on liability concerned 
informed consent: 
                                                 
11 Hannemann also argued that Boyson was negligent because 
he did not tell Hannemann to go see a medical doctor.  But see 
Kerkman 
v. 
Hintz, 
142 
Wis. 2d 404, 
421, 
418 
N.W.2d 795 
(1988)("[W]e hold that a chiropractor does not have a duty to 
refer a patient who is not treatable through chiropractic means 
to a medical doctor.").   
No. 
2003AP1527   
 
36 
 
What did the doctor not do?  He didn't recognize 
the problem and he didn’t inform on that Saturday 
morning, he did not inform Gary Hannemann of the risk 
that he was about to confront with another adjustment.  
He did not tell him, Gary it’s a known fact that there 
is an association between cervical adjustment and 
people who have strokes.  He did not tell him you had 
developed very strange neurological symptoms that may 
indicate that you're in the process of having a 
neurovascular injury.  He did not tell him there are 
options, maybe you should go to a medical doctor, 
maybe we should do nothing.   
What he did is he decided to proceed with an 
adjustment, that is exactly what he did. . . . He 
didn't talk to Gary about the risks.  He didn’t do a 
complete neurological and orthopedic exam. . . . [H]e 
didn't tell Gary to get medical help.   
(Emphasis added.)  
¶65 Thus, throughout this entire trial, the jury was told 
that Boyson provided negligent treatment because he failed to 
obtain proper informed consent.  The jury was informed by an 
expert witness and Hannemann's attorney that failure to obtain 
informed consent was negligent treatment because it was a 
violation of the standard of care.  The circuit court, by 
instructing the jury as to negligent treatment and informed 
consent, but only submitting a special verdict on negligent 
treatment, reaffirmed the theory that failure to obtain informed 
consent violated the standard of care and constituted negligent 
treatment.  While there was some argument that Boyson provided 
substandard treatment in failing to perform proper tests and 
that any cervical adjustment on a patient with Hannemann's 
symptoms 
would 
have 
constituted 
negligent 
treatment, 
the 
No. 
2003AP1527   
 
37 
 
informed consent argument was by far the strongest, most 
extensive argument on liability put forth to the jury.   
¶66 The circuit court and counsel for Hannemann both 
conflated the standards for negligent treatment with the 
standards for informed consent.  As discussed supra, negligence 
in treatment is measured by the standard of care in the 
chiropractic community, i.e., what a reasonable chiropractor 
would do.  In contrast, the obligation to obtain informed 
consent is measured by what risks a reasonable patient would 
want to know and whether a reasonable patient so informed would 
consent to the procedure.  The jury was given two independent 
bases upon which to find liability, but was not required to find 
the ultimate material facts required for liability under one 
theory (failure to provide informed consent) and was further 
told that finding liability under that theory resulted in the 
liability under the other (negligent treatment).  In essence, 
the case was argued to the jury as an informed consent case but 
the jury was asked to submit a verdict on negligent treatment.   
¶67 Given the nature of the error here, we cannot say 
beyond a reasonable doubt that a rational jury would have found 
that Boyson provided negligent treatment had a separate special 
verdict on informed consent been submitted.  Simply put, we do 
not know why the jury found that Boyson provided negligent 
treatment.  The legal error here is so intertwined with the 
verdict rendered that we cannot conclude beyond a reasonable 
doubt that a rational jury would have found Boyson provided 
negligent treatment absent the error.  As such, we cannot 
No. 
2003AP1527   
 
38 
 
conclude that the failure to separately submit a special verdict 
on informed consent did not contribute to the verdict that was 
obtained.  Therefore, we cannot conclude that the error was 
harmless.   
V. 
CONCLUSION 
¶68 In sum, we hold that negligent treatment and failure 
to obtain informed consent in the context of chiropractic 
malpractice are two different issues that require separate 
verdict questions.  We conclude that although the practice of 
chiropractic and the practice of medicine are distinct health 
care professions, the obligation of the practitioners of both to 
disclose the risks of the treatment and care they provide should 
be the same.  While the actual disclosures will inevitably vary 
between doctors and chiropractors, the nature of the duty and 
limitations thereon 
should 
be the 
same.  
A 
patient of 
chiropractic has the same right as a patient of medical practice 
to be informed of the material risks of the proposed treatment 
or procedure so that he may make an informed decision whether to 
consent to the procedure or treatment.  As such, we hold that 
the scope of a chiropractor's duty to obtain informed consent is 
the same as that of a medical doctor.   
¶69 Furthermore, we conclude that the circuit court's 
failure to submit a separate special verdict on informed consent 
after separately instructing the jury on negligent treatment and 
informed consent constituted prejudicial error.  We therefore 
affirm the decision of the court of appeals reversing part of 
No. 
2003AP1527   
 
39 
 
the judgment of the circuit court and remanding the case for a 
new trial.12 
By the Court.—The decision of the court of appeals is 
affirmed.  
¶70 DAVID T. PROSSER, J., did not participate.   
 
 
  
 
                                                 
12 As the parties conceded during oral argument that the 
measure of damages is the same under either a negligence theory 
or an informed consent theory of liability, the trial on remand 
should be limited to the issue of liability.   
No.  2003AP1527.lbb 
 
1 
 
 
¶71 LOUIS B. BUTLER, JR., J.   (dissenting).  The majority 
correctly concludes that negligent treatment and failure to 
obtain 
informed 
consent 
in 
the 
context 
of 
chiropractic 
malpractice are two different issues that require separate 
verdict questions.  Majority op., ¶¶2, 68.  I therefore join 
that portion of the decision relating to the scope of the 
chiropractor's duty to obtain informed consent.  I also agree 
with and join the majority's conclusion that the circuit court's 
failure to submit a special verdict on informed consent after 
separately instructing the jury on negligent treatment and 
informed consent constituted error.  Majority op., part IV.B.  I 
write 
separately 
because 
I 
disagree 
with 
the 
majority's 
conclusion that the trial court's error in failing to submit a 
special verdict on informed consent was prejudicial.  Majority 
op., part IV.C.  I therefore respectfully dissent.   
¶72 The majority correctly notes that an error does not 
require reversal unless it affects the substantial rights of the 
party seeking to set aside the judgment.  Majority op., ¶57.  In 
determining whether the error is prejudicial or harmless, we 
apply the same test for harmless error in civil cases as in 
criminal cases.  Town of Geneva v. Tills, 129 Wis. 2d 167, 184-
85, 384 N.W.2d 701 (1986).  Nevertheless, the harmless error 
test is not easy to articulate or apply.  See State v. Hale, 
2005 WI 7, ¶¶60-61 n.9, 277 Wis. 2d 593, 691 N.W.2d 637.   
No.  2003AP1527.lbb 
 
2 
 
¶73 As I indicated in my concurring opinion in Hale, most 
constitutional errors13 are analyzed using the basic harmless 
error test set forth in Chapman v. California, 386 U.S. 18, 24 
(1967), reh'g denied, 386 U.S. 987 (1967).  Hale, 277 Wis. 2d 
593,  ¶111 (Butler, J., concurring).  For these types of errors, 
the analysis begins with an evaluation of the type of error and 
the harm it is alleged to have caused in order to determine 
whether the error did not contribute to the verdict obtained 
beyond a reasonable doubt.  Id.  The appropriate standard for 
such errors is not whether there is sufficient evidence, absent 
the error, to support the verdict.  Id. (citing State v. Weed, 
2003 WI 85, ¶¶28-32, 263 Wis. 2d 434, 666 N.W.2d 485).   
¶74 Some errors are considered "structural" in nature, and 
are considered so fundamental and pervasive that they require 
reversal without regard to the facts or circumstances of the 
particular case.  Id., ¶110 (citing Chapman, 386 U.S. at 23 n.8; 
Delaware v. Van Arsdall, 475 U.S. 673, 681 (1986); Neder v. 
United States, 527 U.S. 1, 8 (1999)).  These errors include a 
complete denial of counsel,14 a biased trial judge,15 racial 
                                                 
13 Examples 
of 
such 
errors 
include 
the 
following: 
Confrontation Clause violation (Delaware v. Van Arsdall, 475 
U.S. 673, 684 (1986)); illegally seized evidence (Fahy v. 
Connecticut, 375 U.S. 85 (1963), and Gilbert v. California, 388 
U.S. 263 (1967)); the right to consult with counsel (Satterwhite 
v. Texas, 486 U.S. 249 (1988)); involuntary confessions (Arizona 
v. Fulminante, 499 U.S. 279 (1991)); and comments on a 
defendant's silence (Chapman v. California, 386 U.S. 18 (1967), 
reh'g denied, 386 U.S. 987 (1967)).  
14 Johnson v. United States, 520 U.S. 461, 468 (1997). 
15 Tumey v. Ohio, 273 U.S. 510 (1927). 
No.  2003AP1527.lbb 
 
3 
 
discrimination in the selection of a grand jury,16 denial of 
self-representation at trial,17 denial of a public trial,18 and a 
defective reasonable-doubt instruction.19  Id. (citing Neder, 527 
U.S. at 8.)  
¶75 A yet third classification of harmless error involves 
the type of error that by its very nature lends itself to a form 
of an "outcome determinative" approach.  See Id., ¶¶112-13.  
This third class of error includes ineffective assistance of 
counsel20 and errors in jury instructions.21  Id.  For such 
errors, the court looks at whether there is a reasonable 
probability that the jury verdict would have been the same 
absent the error.22  Id., ¶112.  A reasonable probability is one 
sufficient to undermine confidence in the outcome.  Id.  See 
also United States v. Bagley, 473 U.S. 667, 682 (1985).   
¶76 I conclude that the failure to submit a special 
verdict on the question of informed consent after separately 
                                                 
16 Vasquez v. Hillery, 474 U.S. 254 (1986). 
17 McKaskle v. Wiggins, 465 U.S. 168 (1984). 
18 Waller v. Georgia, 467 U.S. 39 (1984). 
19 Sullivan v. Louisiana, 508 U.S. 275 (1993). 
20 Strickland v. Washington, 466 U.S. 668 (1984).   
21 Neder v. United States, 527 U.S. 1 (1999); Yates v. 
Evatt, 500 U.S. 391 (1991); and Pope v. Illinois, 481 U.S. 497 
(1987). 
22 While the burden of proof is normally on the beneficiary 
of the error in harmless error cases, it shifts to the defendant 
in ineffective assistance of counsel cases.  Compare Chapman, 
386 U.S. at 24, with Strickland, 466 U.S. at 694. 
No.  2003AP1527.lbb 
 
4 
 
instructing the jury on both negligent treatment and informed 
consent falls within the third class of harmless error.  In 
looking at the nature of the error and the harm it is alleged to 
have caused, the failure to give a special verdict after 
instructing a jury on a specific issue more closely approximates 
the type of error in failing to instruct a jury in the first 
instance than other types of trial errors.  In both situations, 
the jury has been deprived of certain information upon which to 
base its decision.  Since we cannot look subjectively into the 
minds of the jurors23 when an error occurs in the verdict form, I 
would apply the harmless error analysis adopted for jury 
instruction errors by the United States Supreme Court in Neder 
and by our court in State v. Harvey, 2002 WI 93, ¶47, 254 
Wis. 2d 442, 647 N.W.2d 189.  I would approach the inquiry by 
looking at whether the force of evidence, presumably considered 
by the jury in accordance with the instructions, was so 
overwhelming that we must conclude that the verdict would have 
been the same had the jury received the proper verdict form.  
Hale, 277 Wis. 2d 593, ¶113 (citing Yates v. Evatt, 500 U.S. 
391, 404-05 (1991), (Butler, J., concurring).  
¶77 This is not the first time our court has had to 
determine whether a jury verdict could be supported when the 
jury was faced with alternative methods of proof.  In State v. 
Crowley, 143 Wis. 2d 324, 422 N.W.2d 847 (1988), a jury found 
the defendant guilty of aggravated battery of a disabled person.  
Id. at 327.  However, the State attempted to prove its case on 
                                                 
23 See Yates, 500 U.S. at 404-05. 
No.  2003AP1527.lbb 
 
5 
 
alternate grounds, and it was not clear on which ground the jury 
convicted.  First, the State tried to establish that the 
defendant's conduct directly created a high probability of great 
bodily harm.  Id. at 328.  Alternatively, the State contended 
that because the victim had a physical disability, if the 
evidence established the defendant's intent was to inflict 
bodily harm on a disabled person, then the defendant's conduct 
presumptively created a high probability of great bodily harm.  
Id.   
¶78 This court concluded that when alternative methods of 
proof resting upon different evidentiary facts are presented to 
a jury, it is necessary for an appellate court to conclude that 
the evidence was sufficient under both of the alternative modes 
of proof in order to uphold the verdict.  Id. at 329.  While the 
court recognized that it was unclear which mode of proof the 
jury relied upon, the court nevertheless reasoned that it was 
obliged to search the record in an effort to determine whether 
the evidence was sufficient under each mode of proof.  Id. at 
331, 334.  The court summarized the rule to be applied as 
follows:  "[T]he rule . . . 'requires a verdict to be set aside 
in cases where the verdict is supportable on one ground, but not 
on another, and it is impossible to tell which ground the jury 
selected.'"  Id. at 334-35 (quoting from United States v. Sales, 
725 F.2d 458, 459 (1984)).  See also Yates, 354 U.S. 298; Zant 
v. Stephens, 462 U.S. 862 (1983); Stromberg v. California, 283 
U.S. 359 (1931).  The court ultimately concluded that there was 
No.  2003AP1527.lbb 
 
6 
 
sufficient evidence under either method or mode of proof to 
sustain the jury's verdict.  Crowley, 143 Wis. 2d at 345.  
¶79 Similarly, in State v. Caldwell, 154 Wis. 2d 683, 454 
N.W.2d 13 (Ct. App. 1990), petition for review denied, 457 
N.W.2d 324 (unpub. table decision) (1990), the court of appeals 
was confronted with a conviction for obstructing an officer.  
The trial 
court instructed 
the jury 
that 
the 
crime of 
obstructing could be committed in alternative ways: by making 
more difficult the performance of the officer's duties or by 
knowingly giving false information to the police with intent to 
mislead.  Id. at 690.  Citing Crowley, the court of appeals 
reasoned that for the resulting conviction to stand, the 
evidence would have to be sufficient under both modes of proof.  
Id. at 691.  The court ultimately determined that the evidence 
was sufficient for the jury to convict under either theory of 
obstruction and affirmed the conviction.  Id. at 692, 695. 
¶80 Neither Crowley nor Caldwell was decided using a 
harmless error analysis.  Nevertheless, both decisions provide 
an analytical framework that fits well under the harmless error 
test.  Like this case, both cases involve a general verdict even 
though the jury was presented with alternative grounds for 
reaching its decision.  We are not presented with a situation 
where the verdict is supportable on one ground, but not another, 
and it is impossible to tell which ground the jury relied upon.    
Instead, by determining whether there was sufficient evidence 
under either method of proof, this court necessarily reaches the 
question of whether the evidence is so overwhelming that we must 
No.  2003AP1527.lbb 
 
7 
 
conclude that the verdict would have been the same had the jury 
received the proper verdict form.  See Hale, 277 Wis. 2d 593, 
¶113 
(citing 
Yates, 
500 
U.S. 
at 
404-05), 
(Butler, 
J., 
concurring).  
¶81 Ample evidence was offered at trial that Hannemann 
received 
negligent 
treatment 
from 
Boyson 
following 
a 
chiropractic adjustment to his lower back and neck.  Subsequent 
to the treatment, Hannemann developed numbness and tingling in 
his leg and under his foot.  After complaining of the numbness, 
Boyson performed a second adjustment.  Ultimately, Hannemann was 
unable to move one side of his body and experienced urinary 
tract problems.  He was admitted to the emergency room and 
diagnosed as having suffered a stroke.  Hannemann's expert 
witness testified that the treatment performed by Boyson fell 
below the chiropractic standard of care because Boyson did not 
perform a series of diagnostic tests that would indicate whether 
a patient was susceptible to neurovascular injury.  While that 
evidence was disputed, we must resolve sufficiency of the 
evidence questions in the light most favorable to the verdict.  
State v. Burkman, 96 Wis. 2d 630, 643, 292 N.W.2d 641 (1980).  I 
conclude that there was overwhelming evidence to support the 
jury's 
verdict 
with 
respect 
to 
the 
negligent 
treatment 
alternative. 
¶82 Regarding 
informed 
consent, 
the 
evidence 
was 
undisputed that Boyson did not warn Hannemann that chiropractic 
treatment carried a risk of stroke or other neurovascular 
injuries.  Hannemann's expert witness testified that there were 
No.  2003AP1527.lbb 
 
8 
 
no informed consent forms in the records.  The expert testified 
that informed consent should include a warning to the patient 
that one of the risks of injury of chiropractic treatment 
includes stroke.  Once again, while Boyson disputed the 
evidence, overwhelming evidence is present in the record that 
supports the jury's verdict with respect to the informed consent 
alternative. 
¶83 Because the evidence is sufficient under either method 
of proof, I conclude that the error in failing to submit a 
special verdict to the jury on the question of informed consent 
is harmless.  I would therefore reverse the court of appeals, 
and affirm the trial court.  Accordingly, I respectfully 
dissent. 
  
 
 
 
No.  2003AP1527.lbb 
 
 
 
1