Prosecuting, Mr Price told the jury that Mrs Crown was killed the day before and that male DNA matching David Newton's profile was discovered by scientists in 2023.
Using a DNA testing technique that was not available then, police were able to "cast doubt on David Newton's claims that he hadn't seen [Mrs Crown] on the day, or days, before her death".
The prosecution said the reason why Newton went to Mrs Crown's home and killed her were "not matters that the prosecution need prove".
Detective Superintendent Iain Moor from Cambridgeshire Police said the force had apologised to Mrs Crown's family for "mistakes" during the initial investigation in 2013.
John Payne, the husband of Mrs Crown's niece, found her in her hallway on 13 January 2013.
