The article in the AM New York
https://www.amny.com/news/jogger-kil...ens-1.16947588 says:
The defense said the May 2016 stop of Lewis was unlawful because the cops didnt have probable cause to approach him. But prosecutors said the stop and questioning of Lewis was permissible since it was based on a 911 call about someone possibly trespassing or loitering in backyards.
The defense was trying to say that the DNA was only available because of this unlawful stop in May 2016. The article also says the defense is raising all of this in the event they need to appeal a guilty verdict.
This article,
https://www.thedailybeast.com/he-confessed-to-karina-vetranos-murder-but-did-he-do-it, also has info about possible flaws with the DNA but I'm not sure if those were part of today's motion. The AM New York article gives the story about how they caught him but the Daily Beast article gives a different accounting, based on court testimony.