Factual error: Backdoors of a police car can not be opened from the inside.
Perishable - S4-E9
Factual error: Lydia tells Stiles that as a child she was so obsessed with the book "The Little Mermaid" and insisted on being called Ariel for months. The thing is that the character wasn't named in the book, she was only given the name Ariel in the Disney film.
Factual error: The operator that receives the 911 call only sends the police, when in actuality if a caller is silent during their call, the operator has to send out all emergency services.