Thank you cw028. Who called the police?
That I don't know. But...think about the neighbor seeing her at 3:45 am. Could they have called police due to a noise complaint? The downstairs neighbors weren't too fond of her keeping late hours. Why did they say that in the first place? Perhaps the noise didn't stop after police came and that angered the neighbor?
Or perhaps she was fighting with whoever she was with that night. Police are called for a domestic dispute. Police check it out and assume everything is ok. When they leave, it escalates? They keep that police report under wraps because it makes the dept look VERY bad??
These are just some theories I have.