You Kill Me - S8-E8
Character mistake: While looking at the evidence that was knocked onto the floor, Greg picks up a woman's shoe in his bare hand causing his finger prints to get on it. When investigating a crime, even one in a "whodunit" game, he should have been wearing gloves.
Answer: The episode on CSI:NY was called "Love Runs Cold" and first aired on October 4, 2006 (Season 3, Episode 3) and involves the investigation of a model found stabbed to death by an ice dagger.
OneHappyHusky