I strongly agree with 4honor.........I am a mandatory reporter myself. PLEASE help her to understand that she can go to any teacher or counselor at school to tell them what's going on. As for the cops....if the same scenario ever happens again (and they try to tell you the same thing again), remind them of what their duty is (to serve and protect) and your daughter needs protection NOW. Tell them that the last time you requested them to go to the home (and there was nothing they could do), she was beaten up by her mother and you are fully aware that they are mandatory reporters and have a duty to act.
One thing to keep in mind.......regardless of whom she opens up to, once she does tell someone and the
BM finds out, it very likely will get worse for your daughter. I know how desperately you want to protect your daughter and keep her from harm, but this may be a 'necessary evil', in that this is the only way to get the BM exposed. If you don't, she will continue to beat on the child regardless, and eventually she won't need any excuse.
I don't know what state you're in, but here in IA if a mandatory reporter is aware that an act of abuse is suspected or occurred, they fail to report it, and it is determined that they knew and did nothing, they can receive jail time and/or $25,000 fine. Not something I'm willing to risk myself and my family for, so if I ever even have a suspicion, you can bet I will report it, even if it is eventually deemed unfounded. You might want to research your MR laws and 'strongly remind' the cops what their duty is and what the repercussions might be if they fail to act.
One other thing regarding law enforcement........if at
any time you feel your daughter might be at risk, you can call the local LEA and ask for a 'welfare check'. What they will do is go to the home and check on her to make sure she's okay. If the BM is home, she will no doubt give the cops some song and dance, but at least it will put her on notice that she's being watched. And I'm fairly certain you can ask the cops NOT to give your name as the requesting party, but you better check into that. And if, for whatever reason, they feel she is in 'imminent danger', they have the authority to remove the child from the home. If that were to happen, make sure they know you have
joint custody and/or
visitation rights and that the child can come to your home so that they don't have to put her into the foster system.