Title: Commonwealth v. Cameron
Citation: N/A
Docket Number: SJC-11835
State: Massachusetts
Issuer: Massachusetts Supreme Court
Date: October 28, 2015

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SJC-11835 
 
COMMONWEALTH  vs.  RONJON CAMERON. 
 
 
 
Berkshire.     September 10, 2015. - October 28, 2015. 
 
Present:  Gants, C.J., Spina, Cordy, Botsford, Duffly, 
& Hines, JJ. 
 
 
Rape.  Deoxyribonucleic Acid.  Practice, Criminal, New trial. 
 
 
 
 
Indictments found and returned in the Superior Court 
Department on October 29, 1999. 
 
 
The cases were tried before Thomas J. Curley, Jr.; a motion 
for a new trial, filed on October 8, 2009, was considered by 
John A. Agostini, J., and a motion for reconsideration, filed on 
January 15, 2013, was also considered by him. 
 
 
After review by the Appeals Court, 86 Mass. App. Ct. 1113 
(2014), the Supreme Judicial Court granted leave to obtain 
further appellate review. 
 
 
 
Laura Chrismer Edmonds for the defendant. 
 
Joseph A. Pieropan, Assistant District Attorney (Paul J. 
Caccaviello, Assistant District Attorney, with him) for the 
Commonwealth. 
 
Stephanie Roberts Hartung, for New England Innocence 
Project, amicus curiae, submitted a brief. 
 
 
2 
 
 
CORDY, J.  In April, 2003, a jury found the defendant, 
Ronjon Cameron, guilty on two indictments charging rape, in 
violation of G. L. c. 265, § 22 (b).  As part of its case 
against the defendant, the Commonwealth offered in evidence a 
laboratory report regarding the presence of seminal residue on 
the complainant's underwear.  The Commonwealth also offered 
testimony to suggest that there had been a transfer of semen 
from the defendant onto the complainant's underwear during the 
rape.  Forensic deoxyribonucleic acid (DNA) testing performed 
before trial indicated the presence of two male sources of the 
seminal residue on the underwear.  Testing as to the primary 
source excluded the defendant.  An expert testified on behalf of 
the Commonwealth and described the secondary source as both 
"inconclusive" and as neither including nor excluding the 
defendant.  The defendant was convicted and sentenced to a term 
of from twelve to sixteen years in State prison. 
 
In October, 2009, the defendant filed a motion for a new 
trial, which was denied.  In January, 2013, he filed a motion to 
amend and reconsider his motion for a new trial, based primarily 
on DNA testing performed by an independent laboratory, Bode 
Technology (Bode).  Bode's analysis, using short tandem repeat  
(STR) testing on sixteen loci,1 revealed that the secondary 
                                                          
 
1 The test employed by Bode is a more discerning test than 
was available at the time of the trial in 2003. 
3 
 
source, which the Commonwealth's expert had, at trial, 
attributed to a male donor, was in fact female DNA to which the 
defendant was excluded as a possible contributor.  As part of 
the same motion, the defendant argued that he had been deprived 
of the effective assistance of counsel during trial because 
trial counsel failed (1) to challenge the admissibility of the 
DNA testimony and (2) to retain a DNA expert to explain that he 
should have been excluded as the secondary source of the sample 
at trial.  Without a hearing, a Superior Court judge (who was 
not the trial judge) denied the defendant's motion, concluding 
that "the defendant has not established that the newly available 
evidence would 'probably have been a real factor in the jury's 
deliberations'" (citation omitted).  In an unpublished decision 
pursuant to its rule 1:28, the Appeals Court affirmed the 
denial, determining that "the defendant has not met his heavy 
burden of demonstrating that the judge abused his discretion in 
denying his motion."  Commonwealth v. Cameron, 86 Mass. App. Ct. 
1113 (2014). 
 
We granted the defendant's application for further 
appellate review to consider his claim that the newly available 
DNA evidence warrants a new trial.  Given the importance of the 
existence of a secondary source of male DNA to corroborate the 
testimony of the complainant that the defendant had raped her, 
we conclude that the newly available DNA evidence that 
4 
 
conclusively excludes the defendant as a possible donor would 
likely have been a real factor in the jury's deliberations.  
That evidence would have cast doubt on the credibility of the 
complainant and rendered the Commonwealth's strongest 
corroborative evidence inadmissible.  Had the new evidence been 
available at trial, there is a substantial risk that the jury 
would have reached a different conclusion.  The defendant, 
therefore, must be given a new trial.2 
 
1.  Background.  The prosecution presented its case 
primarily through the testimony of the complainant.  Defense 
counsel called only one witness, the defendant.  As the 
Commonwealth acknowledged during closing argument, "[C]learly 
credibility is at the forefront of this case.  Credibility and 
believability of [the complainant]." 
 
The complainant testified that, on September 13, 1999, the 
defendant raped her, both vaginally and anally, in the apartment 
of her then boy friend.  She testified that she thought the 
defendant had ejaculated.  After the rape, the complainant put 
her clothes back on and left the apartment.  At the time, the 
complainant was wearing a dress, white shorts, and underwear. 
 
Two days after the alleged rape, the complainant went to 
the police station to report the assault.  As part of the 
                                                          
 
2 We acknowledge the amicus brief submitted by the New 
England Innocence Project. 
5 
 
detective's preliminary investigation, he took the underwear and 
the dress that the complainant said she had worn on the night of 
the purported attack.3 
 
On September 20, seven days after the alleged rape, the 
complainant went to a hospital.  At the hospital, the 
complainant was examined by Dr. Mark Liponis.  Liponis testified 
that the complainant reported that the man who raped her had 
ejaculated, but that she was uncertain as to where he had 
ejaculated.  The rape kit, with Liponis's findings, along with 
the confiscated clothing, was transported to the State police 
crime laboratory in Sudbury. 
 
Thomas Sendlenski, a chemist at the laboratory, testified 
that the underwear showed signs of seminal residue, which was 
collected for testing.  Sendlenski testified that the sample in 
question could only have been deposited by a male.  The sample 
was sent for DNA testing to Cellmark Diagnostics, a laboratory 
which has since become Orchid Cellmark (Orchid).  Sendlenski 
also testified about the scientific concept known as "transfer."   
As he described to the jury, transfer is an exchange of 
materials between two items that come in contact with one 
another. 
                                                          
 
3 The complainant could not find the white shorts she had 
been wearing. 
6 
 
 
At Orchid, Kathryn Colombo, a DNA analyst, performed DNA 
tests on the seminal residue samples collected from the 
underwear.  Colombo testified that she performed a Y-chromosome 
STR test with regard to the sample she received.  She reported 
that the data from that test indicated the presence of DNA from 
at least two males.  As part of her testimony, Colombo relied on 
a chart she created in connection with her analysis, which was 
presented to the jury.  There was a primary source, "of which 
[the defendant] was excluded," and a secondary source, about 
which "no conclusion could be made."  Colombo went on to 
explain: 
"And the secondary source, the fourteen observed at 
the DYS nineteen is consistent with the standard of 
[the defendant].  At the three eighty-nine one region, 
just by a coincidence, [the defendant] has the same 
type that was observed in the evidence sample, and it 
could be that that type is present and it's being 
masked by the primary source. 
 
"There was no type determined or found at the three 
eighty-nine two region, so we can't draw a conclusion 
at this region between the standard of [the defendant] 
and the evidence item. 
 
"And then, at the DYS three ninety region, [the 
defendant] is a twenty-four.  We obtained just a 
twenty-one at that region for the evidence.  There is 
no twenty-four present.  However, we know that 
sometimes with these systems we may lose types.  So, I 
-- I'm not saying that we did in this case, I'm just 
saying that we can't make that determination about the 
secondary source, we can't make any conclusion about 
the secondary source." (Emphases added.) 
 
7 
 
 
The prosecutor then asked, "So, is the bottom line, as far 
as the secondary source goes, that your analysis is not able to 
include him as a donor of seminal material to the underwear nor 
exclude him?"  Colombo answered, "That's correct." 
 
During cross-examination of the complainant, defense 
counsel impeached her testimony, challenging her memory of the 
events of September 13 and her relationship with the defendant, 
and questioning why it had taken so long for her to report the 
rape.  The defendant has maintained his innocence throughout 
these proceedings.  He testified that he did not see the 
complainant on the day in question, and he denied any sexual 
contact between himself and the complainant. 
 
2.  Discussion.  The defendant argues that he is entitled 
to a new trial based on (1) the newly available DNA evidence, 
excluding him as the source of any of the DNA residue on the 
complainant's underwear; (2) ineffective assistance of counsel; 
and (3) the admission of false evidence in violation of his 
Federal and State due process rights.  When reviewing a lower 
court's ruling on a motion for a new trial, we "examine the 
motion judge's conclusion only to determine whether there has 
been a significant error of law or other abuse of discretion."  
Commonwealth v. DiBenedetto, 458 Mass. 657, 664 (2011), quoting 
Commonwealth v. Grace, 397 Mass. 303, 307 (1986).  See Mass. R. 
Crim. P. 30(b), as appearing in 435 Mass. 1501 (2001).  "Judges 
8 
 
are to apply the standards set out in Mass. R. Crim. P. 30(b) 
rigorously," and "grant such a motion only if it appears that 
justice may not have been done" (quotations and citations 
omitted).  Commonwealth v. Fanelli, 412 Mass. 497, 504 (1992).  
Where, as in the present appeal, the motion judge "did not 
preside at trial, we regard ourselves in as good a position as 
the motion judge to assess the trial record" (quotation and 
citation omitted).  Commonwealth v. Raymond, 450 Mass. 729, 733 
(2008). 
 
In order to prevail on a motion for a new trial on the 
basis of newly discovered evidence, a defendant must meet the 
two-prong test set out in Grace, 397 Mass. at 305-306.  First, 
the defendant must establish that the evidence is "newly 
available" or "newly discovered."4  Commonwealth v. Cintron, 435 
Mass. 509, 516 (2001).  Grace, supra at 305.  Second, the 
defendant must show that the evidence "casts real doubt on the 
justice of the conviction."  Grace, supra.  To show that newly 
available evidence "casts real doubt on the justice of the 
conviction," the defendant must show that "there is a 
substantial risk that the jury would have reached a different 
conclusion had the evidence been admitted at trial."  Id. at 
                                                          
 
4 "The standard applied to a motion for a new trial based on 
newly available evidence is the same as applied to one based on 
newly discovered evidence."  Commonwealth v. Sullivan, 469 Mass. 
340, 350 n.6 (2014), quoting Commonwealth v. Cintron, 435 Mass. 
509, 516 (2001). 
9 
 
306.  The inquiry is not "whether the verdict would have been 
different, but rather whether the new evidence would probably 
have been a real factor in the jury's deliberations."  Id.  The 
Commonwealth contends only that the defendant has failed to 
satisfy the second prong.5  We therefore only consider whether 
the motion judge abused his discretion in concluding that the 
newly available DNA evidence did not cast real doubt on the 
justice of the defendant's convictions. 
 
The prosecution's case relied almost exclusively on the 
complainant's testimony.  The only evidence before the jury that 
had the potential to corroborate the complainant's testimony was 
the DNA evidence.6  The complainant testified that she believed 
the defendant had ejaculated, and the Commonwealth presented 
evidence that there were stains on the underwear and then 
produced expert testimony regarding the DNA testing of those 
stains.  Taken in conjunction with the testimony elicited by the 
Commonwealth regarding transfer, the jury could have concluded 
                                                          
 
5 To be newly available, the evidence must "have been 
unknown . . . and not reasonably discoverable . . . at the time 
of trial," Commonwealth v. Grace, 397 Mass. 303, 306 (1986).  A 
defendant must also "demonstrat[e] that any newly discovered 
evidence is admissible."  Commonwealth v. Weichell, 446 Mass. 
785, 799 (2006).  The motion judge found that the defendant had 
satisfied these requirements, and the Commonwealth does not 
dispute that finding on appeal. 
 
6 Thomas Sendlenski, a chemist at the State police crime 
laboratory, testified that no seminal fluid or sperm cells were 
located on any items in the rape kit.  There were also no bodily 
fluids, hair, or any fibers noted on the dress. 
10 
 
that there was a transfer of semen from the complainant to the 
underwear in question as a result of a rape.  Although the 
primary source of the DNA was not the defendant, the evidence of 
a secondary male source from which the defendant could not be 
excluded was powerfully corroborative.  Indeed, in his closing 
argument, the prosecutor made good use of the existence of a 
secondary source and of the uncertainty of its donor.  
Specifically, he explained that "[w]hether or not [the 
defendant] ejaculated is not relevant to the charges.  But it 
does put part of the evidence in perspective, because if he did 
ejaculate, you have to assume a transfer to [the complainant's] 
underwear.  And while there is a primary source that excludes 
him, there is another stain there which we can't tell you 
excludes him and we can't tell you includes him.  We simply 
can't tell because of the nature of the stain." 
 
Although defense counsel did not object to the admission of 
the DNA evidence at trial,7 and indeed attempted to use its 
                                                          
 
7 Outside the presence of the jury, the trial judge 
questioned the relevance of the deoxyribonucleic acid (DNA) 
evidence, given that the secondary sample was "inconclusive."  
In response, the prosecutor stated:  "Well, I think it -- 
because there's another -- there's a secondary stain there.  I 
think that's actually the probative point."  However, during 
direct examination of Kathryn Colombo, an analyst at Orchid 
Cellmark, the Commonwealth elicited two transcript pages of 
testimony about the meaning and makeup of DNA.  During this 
testimony, the judge requested a sidebar discussion, and 
questioned the prosecutor as to why he was eliciting such a 
11 
 
uncertainty to the defendant's advantage, we note that, had it 
been objected to, it should not have been admitted in the form 
in which it was offered.  In order to weigh effectively the 
value and admissibility of the DNA evidence at trial, we must 
first characterize it.  Our recent decisions lend guidance in 
characterizing DNA evidence and its concomitant potential effect 
on a jury. 
 
The "admissibility of DNA test results should be determined 
on a case-by-case basis."  Commonwealth v. Mathews, 450 Mass. 
858, 871 (2008).  "Generally, a trial judge is accorded 
'substantial discretion in deciding whether evidence is 
relevant,' and whether relevant evidence should be excluded if 
it is less probative than prejudicial."  Id. at 872 n.15, 
quoting Commonwealth v. Talbot, 444 Mass. 586, 589 n.2 (2005).  
Our cases distinguish between "nonexclusion" and "inconclusive" 
DNA testimony.  Evidence that a defendant is not excluded could 
suggest to the jury that a "link would be more firmly 
established if only more [sample] were available for testing."  
Commonwealth v. Nesbitt, 452 Mass. 236, 254 (2008).  Such 
evidence "should not [be] admitted without accompanying 
statistical explanation of the meaning of nonexclusion."  
Commonwealth v. Mattei, 455 Mass. 840, 855 (2010).  On the other 
                                                                                                                                                                                           
response when the defendant was "excluded from one [sample] and 
from the other sample [Colombo] can't draw any conclusions." 
12 
 
hand, "inconclusive" results "provide no information whatsoever 
due to insufficient sample material, contamination, or some 
other problem."  Id. at 853.  Both the motion judge and the 
Appeals Court determined that the Commonwealth properly 
classified the DNA evidence as "inconclusive" rather than 
nonexclusive.  We disagree. 
 
At trial, the Commonwealth, and Colombo, vacillated between 
referring to the DNA analysis of the underwear stain as 
"inconclusive" and as not excluding or including the defendant.  
The latter description goes beyond mere inconclusive results, 
and permits the jury to make an inference about the defendant's 
relation to the sample.  Moreover, Colombo's testimony added to 
the risk that jurors would draw such an impermissible inference 
when she provided the jury with reasons why the defendant's DNA 
might not have matched the DNA on the underwear.  We conclude 
that the DNA evidence presented by the Commonwealth therefore 
must be characterized as nonexclusion evidence. 
 
Due to the high risk of prejudice from the admission of 
inconclusive DNA evidence, the Commonwealth, when presenting 
expert testimony, should avoid the use of nonexclusion that is 
not accompanied by a "statistical explanation of the meaning of 
nonexclusion."  Mattei, 455 Mass. at 855.  Because there was no 
such statistical explanation presented by the Commonwealth, the 
jury were able to draw the inference that a link between the 
13 
 
defendant's DNA and the DNA on the underwear "would be more 
firmly established if only more [sample] were available for 
testing."  Nesbitt, 452 Mass. at 254.8 
 
The Commonwealth further contends on appeal that it did not 
rely on the DNA evidence to support the defendant's convictions, 
as the complainant's testimony did not conclusively establish 
that the defendant ejaculated.  We disagree.  We also conclude 
that any prejudice from the admission of the DNA evidence was 
not cured by defense counsel's cross-examination of the expert 
witness, his closing argument, or the Commonwealth's concessions 
made during its closing argument.9 
                                                          
 
8 Even if the evidence had been identified as inconclusive, 
it was irrelevant and thus improperly admitted.  In Mathews, we 
determined that, when faced with a challenge to the sufficiency 
of the Commonwealth's investigation, "the prosecutor is entitled 
to introduce testimony to demonstrate that [DNA] tests were 
performed and results (even if inconclusive) were obtained."  
Commonwealth v. Mathews, 450 Mass. 858, 872 (2008).  This often 
turns on whether the defendant pursues a Bowden defense at 
trial.  See id.  See also Commonwealth v. Bowden, 379 Mass. 472, 
486 (1980).  However, in circumstances where the defense is not 
related to adequacy of the Commonwealth's investigation, 
"testimony regarding inconclusive DNA results is not relevant 
evidence because it does not have a tendency to prove any 
particular fact that would be material to an issue in the case."  
Commonwealth v. Cavitt, 460 Mass. 617, 635 (2011).  
Here, defense counsel did not raise a Bowden defense, and 
defense counsel's arguments did not relate to the adequacy of 
the Commonwealth's investigation.  Instead, defense counsel 
sought to challenge the credibility of the complainant. 
 
9 On cross-examination, Colombo admitted that the secondary 
source "could include or exclude any number of males in this 
world."  Defense counsel also asked Colombo, "[a]nd you cannot 
say to even a degree of reasonable scientific certainty that he 
14 
 
 
The Commonwealth's presentation at trial underscored the 
importance of the DNA analysis to the case.  The theory offered 
by the Commonwealth in its introduction of the DNA evidence 
related to the stain was that the existence of a secondary male 
sample, although not conclusively attributed to the defendant, 
established that there was a transfer of semen from multiple men 
to the complainant's underwear during the week in question.  
From this, the jury were asked to infer that the stain resulted 
from a semen transfer in the aftermath of what the complainant 
claimed was a rape.  The jury also were permitted to infer that 
the semen was that of the defendant.  Assuming the accuracy of 
the more recent and sophisticated DNA testing performed by Bode, 
which attributed the secondary source to a female and excluded 
the defendant as a possible donor, we conclude that its 
                                                                                                                                                                                           
is the contributor to the secondary source, is that correct?"  
Colombo stated that it was correct.  During closing, defense 
counsel stated, "There were two sources, two male sources, 
neither of which anyone can ever say in a court of law was [the 
defendant's] samples."  Moreover, defense counsel used the DNA 
results as an argument in favor of the defendant:  "I can't 
emphasize enough the value of DNA evidence in a case of this 
nature. . . .  In this case, you have powerful evidence of the 
highest caliber, scientific reliability of DNA evidence that 
exculpates [the defendant]."  And, in the Commonwealth's 
closing, the prosecutor acknowledged:  "I'll tell you that the 
DNA testing is a wash.  It's important for a thorough 
investigation, to be sure, but I'll suggest to you it also lets 
you know that you need to rely upon other evidence in the case. 
. . .  So, while the DNA evidence may make it easier for you, I 
suggest to you that you ought not look for the easy verdict.  
Your obligation is to evaluate all the evidence and apply the 
law the Court gives you." 
15 
 
availability, coupled with its effect on the Commonwealth's 
evidence at the 2003 trial, would have been a real factor in the 
jury's deliberations. 
 
This case is, in many respects, similar to Commonwealth v. 
Cowels, 470 Mass. 607 (2015), and Commonwealth v. Sullivan, 469 
Mass. 340 (2014).  In Cowels, the Commonwealth relied heavily on 
"inconclusive" serological evidence to bolster the testimony of 
its key witness.10  Cowels, supra at 610-611, 620.  The evidence 
presented was made up of blood samples taken from towels seized 
from a bathroom in a witness's apartment.  Id. at 611.  The 
defendants had purportedly visited the witness after committing 
a murder, and washed in his bathroom.  Id. at 609.  We concluded 
that the defendants were entitled to a new trial on the basis of 
DNA testing performed fourteen years after the trial.  That 
testing revealed newly discovered evidence that excluded both 
the defendants and the victim as the source of the blood on the 
towels, and that would have eliminated the towels as evidence 
against the defendants, and could, ostensibly, also have been 
used as a defense at a new trial.  Id. at 618-619.  We explained 
that, "given the towels' role as one of the few pieces of 
physical evidence that corroborated the testimony of a key 
prosecution witness whose credibility was sharply challenged, 
                                                          
 
10 The Commonwealth's expert testified that the blood on the 
towels "could belong to anybody."  Commonwealth v. Cowels, 470 
Mass. 607, 611 (2015). 
16 
 
the towels likely were a real factor in the jury's 
deliberations."  Id. at 608.  There was "consequently a 
substantial risk that the outcome of the trial would have been 
different had the towels been excluded altogether or 
neutralized" through the introduction of the newly discovered 
evidence.  Id. at 618-619.  In that case, the towels, like the 
underwear here, served as the only physical evidence supporting 
the key witness's testimony. 
 
In Sullivan, the defendant was convicted of murder in the 
first degree and armed robbery.  Sullivan, 469 Mass. at 340.  
Two witnesses, one testifying on behalf of the Commonwealth and 
the other on behalf of the defendant, offered conflicting 
testimony as to the killing.  Id. at 342.  The credibility of 
the Commonwealth's witness was challenged.  Id. at 349.  The 
only nontestimonial evidence presented by the Commonwealth to 
corroborate its witness's account was a purple jacket, which was 
purportedly worn during the murder.  Id. at 345.  A chemist 
testified that blood was found on the cuffs of the jacket, and 
such blood was "consistent" with that of the victim.  Id.  Years 
after the defendant had been convicted, newly available DNA 
evidence established that the residue on the cuffs was in fact 
not blood.  Id. at 349.  We affirmed the allowance of the 
defendant's motion for a new trial, agreeing with the motion 
judge that the newly available DNA evidence would have 
17 
 
"eliminated the purple jacket as evidence linking the defendant 
to the crime, and the defendant would have been able to argue 
that there was no physical evidence tying him directly to the 
killing."  Id. at 350, 353. 
 
As was the case in Cowels and Sullivan, the value of the 
newly available evidence in the present case is two-fold.  
First, the evidence tends to bolster the argument that the DNA 
test results presented at trial were erroneous, thereby 
eliminating a piece of evidence that either did or could have 
linked the defendant to the crime.  Second, the newly available 
DNA evidence could be used at a new trial because it would tend 
to contradict the testimony and undermine the credibility of the 
prosecution's key witness, and would transform what had been the 
prosecution's only physical evidence into evidence on behalf of 
the defendant.  As expressed in Cowels and Sullivan, this dual 
quality to the newly available evidence renders this case 
different from many other cases involving newly available 
evidence.  See Cowels, 470 Mass. at 618; Sullivan, 469 Mass. at 
352. 
 
When evidence presented to the jury "is more credible than 
any other evidence on the same factual issue and bears directly 
on a crucial issue before the jury, such as the credibility of 
an important prosecution witness," that evidence is likely to 
function as a real factor in the jury's deliberations.  Cowels, 
18 
 
470 Mass. at 620, quoting Commonwealth v. Tucceri, 412 Mass. 
401, 414 (1992). 
 
Here, the Commonwealth recognized that the fact that there 
appeared to be a secondary male source of the semen was 
consistent with the complainant's testimony that the assailant 
ejaculated during the rape and that the defendant was the 
assailant, even if he could not be ascertained to be the 
secondary source.  The new DNA evidence transforms the existence 
of a secondary source as being consistent with the complainant's 
testimony to being arguably inconsistent with that testimony, 
and that may have been a real factor in the jury's evaluation of 
credibility or, more precisely, whether they were sufficiently 
convinced of the complainant's credibility to find it true 
beyond a reasonable doubt.  This is particularly so where the 
evidence presented by the Commonwealth was not overwhelming, and 
the outcome of the case turned completely on the jury's 
assessment whether the complainant or the defendant was more 
credible. 
 
This is not a case in which the newly available DNA testing 
merely impeaches the complainant's credibility.  Rather, the 
newly available evidence "negates a key piece of physical 
evidence that the prosecution relied on in arguing that the jury 
should credit [the complainant's] testimony."  Cowels, 470 Mass. 
at 621, quoting Sullivan, 469 Mass. at 352.  This is a case in 
19 
 
which the Commonwealth acknowledges that credibility is at the 
forefront.  There is, therefore, no question that the 
complainant's testimony is the "linchpin" of the Commonwealth's 
case.  Cowels, supra at 623.  The DNA evidence presented at 
trial acted to tip the balance against the defendant.  Had the 
new DNA evidence been available at the trial, there is a 
"substantial risk that the jury would have reached a different 
conclusion."  Grace, 397 Mass. at 306.11 
 
3.  Conclusion.  The judgments of conviction are vacated 
and set aside, and the matter is remanded to the Superior Court 
for a new trial. 
 
 
 
 
 
 
 
So ordered. 
                                                          
 
11 In light of this conclusion, we need not reach the 
defendant's ineffective assistance of counsel and due process 
claims.