Also, my friend's girlfriend just said her personal bedroom was intruded by police, and wants just a few minutes to talk to somebody for free on advice of what she should do. I tried googling places for free consultation but it seems like they're all indeed not free at all so I don't know on what to do about her situation either.
A "personal bedroom" is no different than any other part of the world. If the police have reasonable belief a crime is taking place, they have a legal right to enter. Even a citizen can enter private property if an indictable (felony) offense is
actively taking place.
(Canadian law, but I assume the US law is similar)