Testimony Details DNA Results For Children's Exercise Bands In Lindsay Clancy's Murder Trial

Katarina Stashyn is a forensic scientist with the Washoe County Sheriff's Office in Reno, Nevada, who previously worked for the Massachusetts State Police Crime Lab. Stashyn testified in Lindsay Clancy's murder trial in Plymouth today (Wednesday, August 5, day 7) about her analysis of DNA samples from items seized from Clancy's Duxbury home after she killed her three young children on Jan. 24, 2023. 02:15 "DNA stands for deoxyribonucleic acid, and this is genetic information that is stored in our cells. This is information that makes us who we are. It determines how we develop and grow. A person's DNA is inherited approximately half from their mom and half from their dad. DNA is forensically relevant because it is expected that no two individuals will have the same forensic DNA profile." 03:08 "The items tested in this case and in all cases will go through a four-step laboratory process of extraction, quantification, amplification, and detection, and then profiles developed from that laboratory process will be interpreted and compared." 03:48 "Quantification is the second step when we determine a reliable estimate for the amount of DNA in those samples that were extracted, and those values are then used to optimize the rest of the process with the goal to obtain a quality profile for that sample." 04:03 "And the third step, amplification. Can you explain that?" "Amplification is when we make millions and millions of copies of certain areas of DNA to make it able to be detected and visualized." 04:16 "And then detection. What is that?" "And then the fourth step is separation or detection. This is where we separate out all those millions and millions of copies that we made to make them visual. This produces a DNA profile that an analyst is then able to review and interpret." 05:53 "And when you worked on Lab Number 23 01723, evidence involved in the deaths of Cora Clancy, Dawson Clancy, and Callan Clancy, did you follow the standardized protocols and procedures?" "Yes." 08:15 "What were your findings?" "So I'm going to start with a general statement for this report as a whole. The presence of multiple first-degree relatives in a mixture DNA profile can impact overall interpretation, including the determination of the number of contributors and likelihood ratios." 12:01 "Due to the effects of relatedness, it could be difficult to determine number of contributors simply because so much information is shared." "The ends of the yellow exercise band, whether you considered two contributors or three contributors, both of your findings find that Dawson Clancy was a contributor, a potential contributor?" "Both propositions, either two contributors or three contributors, had high inclusionary stats for Dawson Clancy. Correct." 13:54 "So it's a very large probability that Dawson Clancy is a contributor to that mixture?" "It is a large likelihood ratio that provides support for the inclusion of Dawson Clancy to the profile." 16:55 "And what you stated at the end that if Dawson Clancy is one of the contributors, then Callan Clancy and Patrick Clancy cannot be present together in that mixture. Correct?" "Correct." 17:53 "The fact that they're male doesn't necessarily have an effect, but just in general, relatedness has an effect in this case because so much DNA is shared between potential contributors." 19:06 "So basically, if you're examining a profile and it looks like there's five or more, your work stops because of the limitations of your equipment?" "Correct." 19:21 "The swabs from the middle of the exercise band. What was your What were your findings there?" "The DNA profile was interpreted as a mixture of three contributors, including male DNA. The DNA profile from this item is at least 870 trillion times more likely if it originated from Dawson Clancy and two unknown individuals than if it originated from three unknown unrelated individuals. This provides support that Dawson Clancy is included as a contributor to this DNA profile." 22:48 "The middle of the black exercise band, the highest number of possible inclusion was the 1.6 million times more likely if it originated from core Clancy and two unknown individuals, correct?" "Yes, the highest statistic for this item was a likelihood ratio of 1.6 non-million for Cora Clancy." 23:20 "And so when you have the three contributors, and Cora Clancy has the highest likelihood of being a contributor, if you include her in the mixture, the other four members of the family are excluded?" "Correct." 24:54 "The female DNA profile was interpreted as originating from a single contributor. The DNA profile from this item is at least 18 octillion times more likely if it originated from Lindsey Clancy than if it originated from an unknown, unrelated individual."