J-A25005-17

2018 PA Super 14

COMMONWEALTH OF PENNSYLVANIA

v.

ERIC MCCLELLAN 

Appellant

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 IN THE SUPERIOR COURT OF

 PENNSYLVANIA

 No. 2014 EDA 2016

Appeal from the Judgment of Sentence March 1, 2016

In the Court of Common Pleas of Montgomery County 

Criminal Division at No(s): CP-46-CR-0004322-2015, 

CP-46-CR-0008053-2015

BEFORE: OTT, J., STABILE, J., and STEVENS, P.J.E.

CONCURRING OPINION BY OTT, J.: FILED JANUARY 26, 2018

I concur with the majority in the result of this matter. There is no 

question that the evidence presented at trial was sufficient to support the 

convictions. I write separately to express my concern over the use of the DNA 

comparison method referred to as “likelihood ratio,” and trial counsel’s 

agreement to allow such evidence to be presented without apparent 

foundation.

Cognizant that probation or parole officers still need reasonable 

suspicion to search an area, I am not convinced that the search of McClellan’s 

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 Former Justice specially assigned to the Superior Court.
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basement was necessary or proper.1 Nonetheless, I believe that consideration 

is secondary to the issue concerning the likelihood ratio, which ostensibly 

linked McClellan to the gun, thereby providing evidence to support 

constructive possession of the weapon. However, this issue cannot be 

resolved on direct appeal, because all of the evidence regarding the likelihood 

ratio was admitted without objection by Appellant’s counsel. Therefore, any 

investigation into this issue must take place in the context of a Post Conviction 

Relief Act petition.

Testimony at the suppression hearing/bench trial demonstrated the DNA 

samples were taken from the gun in question from four areas that were most 

likely to have been touched by any person: the slide, the grip, the trigger, and 

the magazine. Traditional DNA testing, where a comparison is drawn between 

the sample and the defendant, could not positively link McClellan to the 

weapon. The DNA analysis showed McClellan could not be excluded from 

having touched the gun in those four areas.2 I note that when a positive link 

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1 McClellan’s parole officer, Agent Scott Dominick testified he was aware of 

the basement and had been there once, when he first surveyed the house. 

However, he had never met or spoken with McClellan in the basement. All 

prior meetings between the two took place either in the living room or in 

McClellan’s room. See N.T. Suppression Hearing/Bench Trial, 11/30/15, at 

59.

2 Thomas Walsh, a forensic biologist for NMS Laboratories, testified there were 

similarities between McClellan’s DNA and the DNA obtained from the gun. 

However, those similarities were insufficient to provide a positive match. See

N.T. Suppression Hearing/Bench Trial, 11/20/2015, at 138. 
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is demonstrated using accepted DNA analysis, the result is often related in 

terms of odds in the millions or billions to one – e.g. the likelihood that the 

defendant provided the sample DNA, as opposed to anyone else, is stated as 

a factor of a billion to one, thereby supporting a reasonable doubt standard. 

No such number could be generated linking McClellan to the gun. Initial DNA 

analysis showed three contributors of DNA in each of the four samples. 

Instead, the Commonwealth presented evidence of something referred to as 

the “likelihood ratio.”

Likelihood ratio appears to provide a statistical analysis of the likelihood 

that, in this instance, McClellan was among the three people who provided the

DNA sample analyzed as opposed to three unrelated persons having touched 

the weapon.3 Further statistical analysis was done by an unnamed source to 

determine the likelihood ratio of McClellan versus a relative of McClellan 

having touched the weapon. I find it significant that no DNA sample of any of 

McClellan’s relatives who shared his residence was provided for actual 

analysis. The likelihood ratio is expressed in terms of tens to thousands of 

times more likely, rather than millions or billions of times more likely.

There is no clear explanation in the testimony or exhibits from the 

suppression hearing of how the likelihood ratio is generated from samples that 

otherwise cannot link a person to that sample. This is more concerning 

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3

Initial DNA analysis showed three contributors of DNA in each of the four 

samples.
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considering that the unnamed entity that conducted the likelihood ratio 

calculations was unavailable to explain either its methodology or the 

scientific/statistical principles supporting that ratio. 

A Westlaw search of the term “likelihood ratio” found three cases 

referring to this method of analysis. They are, Commonwealth v. Trieber, 

121 A.3d 435 (Pa. 2015); Commonwealth v. Lyons, 79 A.3d 1053 (Pa. 

2013), and Commonwealth v. Foley, 38 A.3d 882 (Pa. Super. 2012). In 

Trieber, the likelihood ratio was used on canine DNA to establish what breed 

of dog supplied the DNA sample. Our Supreme Court did not rule upon the 

methodology because there was otherwise overwhelming circumstantial 

evidence supporting the defendant’s conviction. In Lyons, the method was 

only mentioned, indicating there needed to be certain calculations done to 

account for the possibility of co-ancestry in the DNA sample.4 Finally, in 

Foley, a panel of our Court stated that if likelihood ratio had been challenged 

as novel science and subjected to a Frye test, it would likely have passed. 

The calculations in Lyons were made by a Dr. Perlin, who had developed 

proprietary software that had been in use in Europe and had helped Britain 

develop its DNA base. I note that the proprietary nature of the software made 

it impossible for the specific methodology to be examined. While it is 

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I believe this type of calculation was performed by the unnamed entity in 

the instant matter.
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impressive that Dr. Perlin’s propriety software has been in use in Great Britain, 

I would be hesitant to rely upon a secret methodology for conviction. In any 

event, there is no indication that Dr. Perlin or his proprietary software was 

used instantly.

In summary, I have concerns regarding the use of likelihood ratio 

evidence. In this matter, the entity that made the calculations was not 

identified and there was no testimony as to how the relevant statistical 

analysis was achieved. I believe prudence dictates that if such evidence is to 

be used in the future, there must be a record developed demonstrating 

methodology and the techniques used to arrive at the conclusion.