Here in the UK the police can issue "a producer" - it's effectively a caution to attend a police station and provide paperwork for something within 7 days. It's usually issued for things like broken lights, worn tyres, etc. You get a form from the officer, get the problem fixed, the mechanic stamps the form, and then you take it to a police station to show you fixed the problem. If you don't show up the police come to your house and arrest you.

They could have given her one of those saying take the paperwork for the windows to the police station any time in the next week. She could have taken a friend with her if she's nervous.

Violence is never the answer in a situation like that. The police officer was entirely wrong.