Women tend to do this. They see the criminal in handcuffs, crying and making a scene and they let emotions take over.
At university we watched a mugger steal our friends hand bag, we chased him and eventually security saw, followed us in the car and his partner did basically a bad ass rugby tackle from the passenger seat of the moving car (dont mess with south african security).
So eventually everything's controlled, hes stopped, in handcuffs, wailing like a fucking witch on fire and when they returned the bag to her she was like "awwwww noooo, he did nothing wrong"
I was so pissed because we chased that fucker for like 2 blocks