Family Law Questions? Ask a Family Lawyer Online.
I'm Lucy, and I'd be happy to answer your questions today. I'm sorry to hear about your dilemma.
The best way for you to help the mother is to appear in court personally and testify as to things you personally observed: when you saw the father using heroin, how he behaved, how the drug changed him, how frequent the use was. It would also help to detail the events that lead to the domestic violence and assault charges. The mother should be able to get police reports and court records to introduce into evidence without your help. But what the judge wants to know is what you experienced - things you saw, heard, experienced. If you don't remember the answer to a question, it's better to say so than to guess. You can explain what caused you to end the relationship, including his behavior after getting treatment. All of that stuff is relevant to his ability to raise a child.
If you're not able to testify, or she's not asking you to do that at this point, you can put it all in writing. Chronological order is usually best. Just say what you remember. Paint a picture of your experiences. The letter should be signed in front of a notary, who can verify your signature under oath. Your own words are really more powerful than anyone else telling you what to say - it'll be more raw, more honest that way.