[General] crime witness

[Silverobama]

The following sentence is from a Chinese-English website where I once studied English. Now, I can't find the link of the website or the sentence online.

The crime witness wouldn't cooperate with the police at first, but after a talk with her lawyer, she agreed to play ball.

I don't think "crime" is needed here. May I have your opinion?

 

[GoesStation]

The sentence works with or without crime, but the meaning changes. The police could be interested in someone who had witnessed something that wasn't a crime.