Cold Case (2003)

Thick as Thieves - S5-E5

Factual error: Look at the area by the door when we see Margot and Spencer in the hotel room in 1989. The light switch is a flat "Decora" switch, and above the door handle is a black box that houses electronics for a "card key" system. The light switch was not introduced until the 1990s, and while the card key system was introduced in 1985, only very expensive hotels afforded the conversion costs - and the hotel they're at isn't exactly the Hilton.