The HONORABLE JAMES M. BURNS, United States District Judge *

for the District of Oregon, sitting by designation.

 The Honorable Donald J. Stohr, District Judge for the 1

Eastern

District of Missouri.

___________

No. 95-3029EA

___________

United States of America, *

 *

 Appellee, *

v. * Appeal from the United States

 * District Court for the Eastern

Kevin Jacobs, aka Maurice * District of Arkansas.

Hawkins, *

 *

 Appellant. *

___________

Submitted: April 9, 1996

Filed: October 3, 1996

___________

Before BEAM and MURPHY, Circuit Judges, BURNS, District Judge. *

___________

BURNS, District Judge.

 On April 7, 1995, a jury convicted Jacobs of conspiracy to commit bank

robbery in violation of 18 U.S.C. § 371 and armed bank robbery in violation

of 18 U.S.C. § 2113. The district court sentenced Jacobs to 60 months

1

imprisonment on the first count and 300 months on the second count, the

sentences to run concurrently and to be followed by a five-year term of

supervised release. Defendant was also ordered to pay restitution in the

sum of $1,609.00.

 Jacobs appeals his conviction and seeks a new trial on the following

grounds:
2

1. The district court erred when it instructed the jury by

reading an incorrect list of overt acts purportedly committed by defendant;

 2. The district court erred when it admitted defendant's

confession into evidence; and

 3. The district court erred when it required defendant to

conduct over the telephone a significant portion of his cross-examination

of the government's main witness against him.

For the reasons articulated below, we AFFIRM Jacobs's conviction.

JURY INSTRUCTIONS

 Jacobs contends he was prejudiced when the district court

misinstructed the jury by reading an incorrect list of overt acts

purportedly committed by defendant. Jacobs further asserts he should have

been permitted to reopen his defense following the court's error.

 After the district court instructed the jury, it discovered its

instructions included an incorrect list of overt acts that were drawn from

one of the government's early drafts of the Indictment. The next morning,

before closing arguments and the jury's deliberations began, the court

informed the jury of its error and re-instructed the jury with the correct

list of overt acts purportedly committed by Jacobs.

 "[P]roperly objected to jury instructions" are reviewed for harmless

error pursuant to Fed. R. Crim. P. 52(a). United States v. Ryan, 41 F.3d

361, 366 (8th Cir. 1994), cert. denied, 115 S.Ct. 1793 (1995). The test

"for determining the adequacy of jury instructions is 'whether the

instructions, when taken as a whole, adequately advise the jury of the

essential elements of the offenses charged and the burden of proof required

of the government.'" United States v. Bishop, 825 F.2d 1278 (8th Cir. 1987)

(quoting United States v. Sherer, 653 F.2d 334, 337 (8th Cir.), cert.

denied, 454 U.S. 1034 (1981)).
3

We are not persuaded by Jacobs's arguments that the court's initial

error prejudiced him or that the court's subsequent action failed to cure

the error. We find the district court's error was harmless "once remedial

action was properly taken," United States v. Nabors, 762 F.2d 642, 648 (8th

Cir. 1985), particularly since the district court cured its error before

counsel began their closing arguments and before the jury began its

deliberations.

 Accordingly, we hold the district court's instructions, taken as a

whole, adequately advised the jury of the essential elements of the

offenses charged and the burden of proof required of the government.

JACOBS'S CONFESSION

 Jacobs asserts the district court erred when it admitted his

confession because his confession was involuntary and coerced. Jacobs also

contends his confession was inadmissible because during the interrogation

he requested and was denied right to counsel in violation of the Sixth

Amendment.

Voluntariness of Jacobs's Confession

 A district court's decision as to whether a defendant's confession was

voluntary is reviewed de novo. United States v. Kilgore, 58 F.3d 350, 353

(8th Cir. 1995)(citing United States v. Johnson, 47 F.3d 272, 275 (8th Cir.

1995)).

 The test for determining the voluntariness of a confession is "whether

the confession was extracted by threats, violence, or direct or implied

promises" to such a degree that defendant's will was overborne, United

States v. Kilgore, 58 F.3d at 353, and "'his capacity of self-determination

critically impaired.'" Sumpter v. Nix, 863 F.2d 563, 565 (8th Cir. 1988)

(quoting Culombe v. Connecticut, 367 U.S. 568 (1961)). The court must

"inquire into
 During the suppression hearing, the district court had 2

access to the unredacted tape of the interview with the Los

Angeles police. A redacted tape containing only Jacobs's

confession and a transcript of that portion of the tape were

later admitted into evidence during trial.

4

the totality of the circumstances in assessing the conduct of law

enforcement officials and the suspect's capacity to resist any of

pressure." United States v. Kilgore, 58 F.3d at 353 (citations omitted).

 The record reflects Jacobs was interrogated for approximately two

hours by the Los Angeles police regarding his possible involvement in a

murder that took place in California. Following that interrogation, he was

interviewed by a special agent for the FBI. During the interview with the

Los Angeles police, Jacobs said he was out of state at the time of the

murder and, as part of his alibi, he stated that he committed armed bank

robbery in Arkansas around the time of the murder. In his later interview

with the FBI agent, Jacobs reiterated that he was in Arkansas robbing a

bank around the time of the murder and also identified himself as one of

the bank robbers in the bank surveillance photographs taken during the

robbery. Jacobs now contends he confessed to the bank robbery and

identified himself in the bank surveillance photographs only after the Los

Angeles police "threatened" him by referring to the possibility that the

murderer might be subject to the death penalty.

 After hearing the testimony of the LAPD officer and the FBI agent who

interviewed Jacobs, and after listening to the tape of the interview with

the Los Angeles police, the district court concluded Jacobs's confession 2

was voluntary. We agree.

 On the interview tape, Jacobs first brings up his participation in the

Arkansas bank robbery on his own initiative long before the officers make

any oblique references to the
 Jacobs does not contend he requested an attorney during his 3

interview with the FBI agent.

5

possibility that the person who committed the murder might be subject to

the death penalty. Later in the interview, Jacobs voluntarily elaborates

on his involvement in the bank robbery as a crucial part of his alibi.

 After reviewing the record and listening to the interview tape, we

find the totality of the circumstances does not demonstrate that Jacobs's

will was overborne or that his capacity for self-determination was

critically impaired. We hold, therefore, the district court did not err

when it concluded Jacobs's confession was voluntary.

Admissibility of Jacobs's Confession

 Jacobs also asserts he was denied his right to an attorney in

violation of the Sixth Amendment even though he asked for one near the end

of his interrogation by the LAPD and, therefore, his confession should not 3

have been admitted as evidence.

 A district court's decision to admit or to suppress a defendant's

confession is reviewed under a clearly erroneous standard. United States

v. Meirovitz, 918 F.2d 1376, 1379 (8th Cir. 1990), cert. denied, 502 U.S.

829 (1991). We must affirm the district court's decision to admit

defendant's confession unless its decision was "'unsupported by substantial

evidence, based on an erroneous interpretation of applicable law, or, in

light of the entire record, we are left with a firm and definite

conviction'" that the district court made a mistake. Id. (quoting United

States v. Jorgensen, 871 F.2d 725, 728 (8th Cir. 1989)).

 At the beginning of the taped interview with the Los Angeles police,

Jacobs was advised of and orally waived his Miranda rights.
6

Jacobs was then interviewed by an FBI agent, was again advised of his

Miranda rights, and waived his rights both orally and in writing.

 During his interview with the Los Angeles police, Jacobs said he would

want a lawyer in the event he had to take a polygraph test. Jacobs did not

request a lawyer at any other time. The district court found Jacobs's

request for an attorney was limited to the specific circumstance of taking

a polygraph test. Jacobs did not take a polygraph test; therefore, Jacobs

was not denied his constitutional right to counsel.

 After listening to the tape and reviewing the transcript of that

portion of the tape, we agree with the district court; therefore, we find

the statements made by Jacobs before and after his request were admissible

as evidence. See Connecticut v. Barrett, 479 U.S. 523, 529 (1987)

(defendant expressed a desire for the presence of counsel only in the event

he had to make a written statement and, therefore, all of defendant's

statements unconnected to making a written statement were admissible). See

also United States v. Boyer, 914 F.2d 144, 146 (8th Cir. 1990) ("[A]

limited invocation of the right to counsel does not preclude the

admissibility of statements a defendant makes which fall outside the

limited invocation."), cert. denied, 499 U.S. 908 (1991).

 In summary, we find nothing in the record to indicate the district

court erred when it concluded Jacobs's confession was voluntary. We also

find the district court's decision to admit Jacobs's confession was

supported by substantial evidence and based on a correct interpretation of

the applicable law. We hold, therefore, the district court did not err

when it admitted Jacobs's confession as evidence.
 Jacobs invokes both Fed. R. Crim. P. 26, which provides 4

"the testimony of witnesses shall be taken orally in open court"

in all trials, and the Confrontation Clause of the Sixth

Amendment, which provides "the accused shall enjoy the right . .

. to be confronted with the witnesses against him"; however, we

find resolution of the constitutional question is sufficient to

lay this issue to rest.

 At a later time during the trial, defense counsel rejected 5

the court's offer.

7

RIGHT OF CONFRONTATION

 Jacobs also contends the district court erred when it required him to

conduct by telephone a significant portion of his cross-examination of

Kimberly Johnson, the government's main witness against him, in violation

of his rights under the Confrontation Clause of the Sixth Amendment.4

Background

 When Johnson was called as a witness at Jacobs's trial, she was

pregnant and close to her delivery date. Her condition was such that she

was too large to sit in the witness box in the usual manner and had to turn

away from the jury. During cross-examination by Jacobs's counsel, the

court called a recess to give Johnson a break. Although she indicated she

wanted to finish testifying despite her discomfort, the court excused her

temporarily and requested an ambulance. Johnson did not return to court

after the noon recess. After the district judge excused the jury for the

day, he advised counsel to consider what they would do if Johnson were

unable to return to court. The court also informed defense counsel they

would be permitted to read into the record portions of Johnson's pretrial

testimony from the suppression hearing in place of cross-examination if

Johnson were unable to return to the stand.5

The following day Johnson's doctor informed the court that
 We do not have an accurate log of the time Jacobs spent 6

cross-examining Johnson; however, the court reporter's notes and

the record reflect Jacobs's cross-examination of Johnson in open

court filled approximately 13 transcribed pages and his crossexamination of Johnson by telephone consisted of approximately 20

transcribed pages.

8

Johnson would have to stay in the hospital for at least two more days and

that she might be unavailable to testify during the following week.

Jacobs's attorney asserted his cross-examination of Johnson was critical

to Jacobs's defense because Johnson was the government's primary witness

against Jacobs. Defense counsel pointed out he had not reached the crux

of his cross-examination when the court excused Johnson. Defense counsel 6

also vigorously argued it was crucial for the jury to have the opportunity

to observe Johnson's demeanor during cross-examination in order to properly

evaluate her credibility, particularly in light of her prior inconsistent

statements and the fact that Johnson's testimony was the core of the

government's case against Jacobs. Jacobs's counsel requested a continuance

until at least the following week. In spite of counsel's objections and

request for a continuance, the court ruled Johnson would be cross-examined

by telephone if she were still unavailable that afternoon.

 When court reconvened, the remainder of Jacobs's cross-examination of

Johnson was conducted over the telephone. Johnson was on the telephone in

the hospital with her lawyer present; the trial judge, defendant, and

counsel were in the judge's chambers; and the jurors were seated in the

jury box listening to Johnson's testimony through speakers in the

courtroom.

The Law

 The Confrontation Clause of the Sixth Amendment "guarantees the

defendant a face-to-face meeting with witnesses appearing before the trier

of fact." Coy v. Iowa, 487 U.S. 1012, 1016
9

(1988). The basic purpose of the Confrontation Clause is "to ensure the

reliability of the evidence against a criminal defendant by subjecting it

to rigorous testing in the context of an adversary proceeding before the

trier of fact," Maryland v. Craig, 497 U.S. 836, 845 (1990), and by giving

defendant the "opportunity, not only of testing the recollection and

sifting the conscience of the witness, but of compelling him to stand face

to face with the jury in order that they may look at him, and judge by his

demeanor upon the stand and the manner in which he gives his testimony

whether he is worthy of belief." Mattox v. United States, 156 U.S. 237,

242-43 (1895). Face-to-face confrontation ensures "'the integrity of the

fact-finding process.'" Coy v. Iowa, 487 U.S. at 1020 (citing Kentucky v.

Stincer, 482 U.S. 730, 736 (1987)).

 Although the Confrontation Clause embraces the principle that the

physical presence of witnesses in a criminal trial and the opportunity for

the fact-finder to observe the demeanor of witnesses are elements that

ensure the reliability of evidence admitted against an accused, the Clause

does not guarantee "criminal defendants the absolute right to a

face-to-face meeting with witnesses against them at trial." Maryland v.

Craig, 497 U.S. at 844, 846. The preference established by precedent for

face-to-face confrontation at trial, Ohio v. Roberts, 448 U.S. 56, 63

(1980), has occasionally given way. Maryland v. Craig, 497 U.S. at 849-50.

Specifically, the Supreme Court has carved out a narrow exception to a

criminal defendant's right to face-to-face confrontation when (1) "denial

of such confrontation is necessary to further an important public policy"

and (2) the necessities of the case require same. Id. at 850. See also

United States v. Benfield, 593 F.2d 815, 821 (8th Cir. 1979) (exceptions

to the Confrontation Clause "should be narrow in scope and based on

necessity or waiver"). The trial court is required to identify the

important state interest and to hear evidence to determine the necessities

of the specific case before abridging a defendant's right to confrontation.

Maryland v. Craig, 497 U.S. at 855-58.
10

Discussion

1. Public Policy

The district court did not identify any state interests that

compelled it to go forward with the cross-examination of Johnson via

telephone. The court may have been concerned about the efficient use of

court resources and/or defendant's rights under the Speedy Trial Act;

however, we can only speculate in the absence of the court's identification

of same. Mere speculation is insufficient to justify abridgement of

defendant's constitutional right to confront his accuser face-to-face in

the jury's presence.

2. Necessities of the Case

A defendant's rights under the Confrontation Clause may be

abridged if a witness is truly unavailable. See e.g., United States v.

Kelly, 892 F.2d 255, 261 (3d Cir. 1989) (videotaped depositions of foreign

witness taken without defendant's presence admissible because witness was

unavailable to testify at trial), cert. denied, 497 U.S. 1006 (1990);

United States v. Mueller, 74 F.3d 1152, 1156-57 (11th Cir.

1996)(depositions of foreign witness admissible because the witness was

unavailable to testify at trial).

When a witness is unavailable due to illness, the Third, Fifth,

and Sixth Circuits have concluded the district court must determine the

necessities of the specific case by weighing "the importance of the absent

witness for the case; the nature and extent of the cross-examination . .

. ; the nature of the illness; the expected time of recovery; the

reliability of the evidence of the probable duration of the illness; and

any special circumstances counselling against delay." United States v.

Faison, 679 F. 2d 292, 297 (3d Cir. 1982). See also Ecker v. Scott, 69

F.3d 69, 72 (5th Cir. 1995) (the court should "engage in a multifactored

analysis"
 The jury had the opportunity to observe Johnson's demeanor 7

during direct examination by the government, cross-examination by

one codefendant, and the partial cross-examination by Jacobs

before Johnson was excused.

11

that considers the Faison factors); Stoner v. Sowders, 997 F.2d 209, 212

(6th Cir. 1993) ("When the question is one of the health of the witness,

there must be 'the requisite finding of necessity' which is 'case specific'

in order to dispense with confrontation in open court.") (quoting Maryland

v. Craig, 497 U.S. at 855). We find the approach of our sister circuits

worthy of emulation.

 Among other things, the district court should have made specific

inquiry into the severity and duration of Johnson's "poor health." Stoner

v. Sowders, 997 F.2d at 212. The district court did not make the requisite

finding that Johnson was sufficiently unavailable to trigger an exception

to the Confrontation Clause; i.e., Johnson "was not dead, beyond the reach

of process nor permanently incapacitated." Ecker v. Scott, 69 F.3d at 71.

Johnson was, in fact, only temporarily unavailable for cross-examination

because of her medical condition. Nothing in the record indicates she

would have been unlikely to recover in a short time or would have been

unable to appear in open court within a reasonable time.

Johnson was the government's primary witness against Jacobs.

Although the jury had the opportunity to observe Johnson's demeanor before

she was excused, a significant portion of Jacobs's cross-examination did 7

not take place in the presence of the jury. In fact, counsel, defendant,

and jurors were all denied the opportunity to observe the facial and

physical expressions that accompanied Johnson's responses to the greater

part of Jacobs's cross-examination. As we have noted before, "in some

undefined but real way recollection, veracity, and communication are

influenced
 In Murphy v. Tivoli, we held that telephone testimony does 8

not qualify as testimony taken in "open court" even though we

acknowledged that a party may read into the record a witness's

deposition taken by telephone if that witness was truly

unavailable to testify at trial. 953 F.2d 354, 359 (8th Cir.

1992).

12

by face-to-face challenge." United States v. Benfield, 593 F.2d at 821.

Jacobs was deprived of this critical face-to-face challenge in the presence

of the jury.

 Jacobs's right to have the jury evaluate Johnson's demeanor

during cross-examination was an important protected interest. Mattox v.

United States, 156 U.S. 237, 242-43 (1895). Although Jacobs's arguments

might wield less power if the jurors, defendant, and defense counsel were

able to view by video monitor the witness's demeanor and "body language"

that accompanied her responses, we are reluctant to tolerate even these

technological variations on "face-to-face" confrontation except when

necessity or waiver have been demonstrated. See e.g., United States v.

Benfield, 593 F.2d at 821; Lam v. Iowa, 860 F.2d 873, 874 (8th Cir. 1988)

(admission of videotape of witness's deposition insufficient to overcome

constitutional violation of defendant's right to confront his accuser

face-to-face in the presence of the jury because the witness's presence

could have been obtained), cert. denied, 490 U.S. 1069 (1989).

 In conclusion, the circumstances of this case do not persuade us

we should endorse cross-examination via telephone either generally or in 8

this particular criminal case. We hold, therefore, the district court

erred when it substituted cross-examination via telephone for in-person

cross-examination in open court without identifying the important state

interests and hearing evidence to determine the specific necessities of

this case that justified abridgement of Jacobs's constitutional right to

confront his accuser face to face.
 Although the government did not raise the issue of harmless 9

error, we may undertake such analysis sua sponte when we think

"the finding of harmlessness is beyond reasonable argument" and

our review of the straightforward record "will prevent an

expensive and futile remand." Lufkins v. Leapley, 965 F.2d 1477,

1481-82 (8th Cir.), cert. denied, 506 U.S. 895 (1992).

13

Harmless Error Analysis

 All errors of constitutional dimension do not automatically call for

reversal. Chapman v. California, 386 U.S. 18, 23 (1967). We review

Confrontation Clause errors under the Chapman harmless- error rule. Coy

9

v. Iowa, 487 U.S. at 1021. See also United States v. Simmons, 964 F.2d 763,

770 (8th Cir.), cert. denied, 506 U.S. 1011 (1992).

 To hold a federal constitutional error harmless, we must declare "the

error was harmless beyond a reasonable doubt." Delaware v. Van Arsdall, 475

U.S. 673, 684 (1986). See also Lufkins v. Leapley, 965 F.2d 1477, 1481 (8th

Cir.), cert. denied, 506 U.S. 895 (1992). Whether the error was harmless

beyond a reasonable doubt "must . . . be determined on the basis of the

remaining evidence" rather than whether the jury's assessment or the

witness's testimony would have changed in the absence of the error. Coy

v. Iowa, 487 U.S. at 1021-22.

 During his interviews with the LAPD and the FBI in California, Jacobs

confessed to the bank robbery in Arkansas. Jacobs also identified himself

in the bank surveillance photograph during his interview with the FBI

agent. This Circuit has consistently followed Wong Sun v. United States,

371 U.S. 471, 489 (1963), in which the Supreme Court held "the guilt of an

accused may stand on nothing more than the defendant's . . . uncorroborated

confession" if the state "has established injury to person or property

caused by the criminal acts of some person." Lufkins v. Leapley, 965 F.2d

at 1482 (citing United States v. Opdahl, 610 F.2d 490, 493 (8th
14

Cir. 1979), cert. denied, 444 U.S. 1091 (1980)). In this instance,

however, Jacobs's conviction stands on much more than his confession.

 Johnson was an important witness for the government. In the presence

of the jury during direct examination, cross-examination by one defendant,

and the part of Jacobs's cross-examination conducted in open court, Johnson

essentially corroborated several material elements of Jacobs's confession:

She was the friend Jacobs said he knew in Arkansas before the bank robbery;

she was the friend Jacobs said he was staying with in Arkansas at the time

of the bank robbery; and she was the woman Jacobs referred to in his

confession who was arrested with the stolen money in the trunk of the car

she was driving. Johnson also readily identified Jacobs as one of the

robbers in the bank surveillance photograph.

 In his cross-examination of Johnson in open court, Jacobs primarily

attacked Johnson's credibility by pinpointing inconsistencies between her

testimony and earlier statements she made to police. The portion of

cross-examination conducted by telephone was cumulative in that it

consisted of more of the same; i.e., Jacobs's cross-examination over the

telephone was essentially a continuation of Jacobs's challenge to Johnson's

credibility and centered on showing inconsistencies between the statements

Johnson made before and during trial relating to details about the sequence

of events leading up to and following the bank robbery. None of Johnson's

testimony, either in court or via telephone, contradicted or cast doubt on

the material elements of Jacobs's confession.

 In the absence of any of Johnson's testimony, the remaining evidence

was still more than "minimally sufficient" to support Jacobs's conviction.

Lam v. Iowa, 860 F.2d at 876. One of the Los Angeles police officers and

the FBI agent, who each conducted separate interviews with Jacobs,

testified to the fact that Jacobs voluntarily confessed and that he offered

his confession as part of
15

his alibi for the murder in California. The jury heard the redacted tape

and read the transcript of Jacobs's confession. A defendant's confession

"has an extraordinary impact on a finder of fact." Lufkins v. Leapley, 965

F-2d at 1482-83 (citing generally Arizona v. Fulminante, 499 U.S. 285

(1991)). "[W]hen a defendant admits a crime, the jury will be tempted to

rest its decision on that evidence alone." Id. The jury in this case,

however, had more than Jacobs's confession. The testimony of the FBI agent

also established that Jacobs identified himself in the bank surveillance

photograph during his interview with the agent. Two employees of the bank

present at the time of the robbery also identified Jacobs in open court as

one of the bank robbers.

 After reviewing the record as a whole, we are convinced beyond a

reasonable doubt the violation of Jacobs's rights under the Confrontation

Clause was harmless error.

CONCLUSION

Based on the foregoing, we AFFIRM Jacobs's conviction.

A true copy.

Attest:

CLERK, U.S. COURT OF APPEALS, EIGHTH CIRCUIT.