My sons dad is on his birth certificate, but we have been separated for 3 plus years after he became abusive, the police have told me not to let him have any contact with my son but does he have any parental responsibilities and will I have to inform him of moving home n my sons school .

Legal advise, to particular cases, must be sought or given directly by an attorney, so I advise you to call your local Free Legal Aid Services. But, generally speaking, from my experiences, if your husbands name is on your son's birth certificate, yes he is legally responsible. That is, if a Court of proper jurisdiction decided what responsibilities he orders of him. Otherwise, he doesn't have to do anything but cause you and your son problems, even with your separation, according to you and your police. You have reason enough being mother to go to court and legalize all your issues, of support, education, and what you consider his behavioral problems. There are parenting and counseling classes the Judge may order him to attend to straighten his attitude out and show respect to your son and you, which may help make your life much easier. Seek out legal advise from an legal aid lawyer, is your best bet. Good Luck!

Have you taken him to court for child support? Has a court ordered custody and visitation?

Of course the legal father has responsibilities, but he also has rights. But both need to be formalized by a family court.

Thanks to both of you for your help. Myself and my sons dad was never married so will that change anything ? Also we have never been to court over our child as he doesn't show any interest in his son only when his trying to get to me so that he can course problems between myself and my new partner. He made so many promises to my son over the phone around Christmas time but we haven't heard from him since. My son is only 7 years old and I think his already given up on his dad as he never mentions him or asks to see him, which I didn't want as I believe children need both parents and I'm happy for my sons dad to see him as long as he doesn't come by me, as in the past he was very violent towards me.

The fact that you were never married doesn't change anything. But if you want to enforce his responsibilities you need to go to court. If you want the freedom to move you need to go to court.