help statemented young adult wants to live with me the father

[saul101]

hi this is my first post and please be kind.
I have a 16 year old son who has mild learning disabilities. he has a SEN and has now said he wants to live with me his father.
I need to know where I stand legally as his mother has said that he can not move. She lives in what I would consider an undesirable place and he and his friend were chased by a group of lads who had a knife his friend was beaten up, I am obviously concerned for his safety.
His mum has said that because of his statement she has sole responsibility for him is this true?
We have looked at a local college that offer the same course that he will be starting in September and they are happy to take him. He has said that he will not get in the car on Friday with his mum and does not want to go back to his mums house. He has been staying with me for all of the summer holidays apart from two weeks where his mum took him on holiday.
To say I am stumped is an understatement. please give me some advice. I just want what is best for my son and feel the move here would be positive for him. there are a few other issues that we have had with my son but I would not like to into them on here.
many thanks in advance.

[deedeelondon]

I'm not an expert but I'm pretty sure that his being statemented does not give your ex sole responsibility. You should take some legal advice - there are many solicitors who will give an initial assessment of your case free of charge. Check online.