I have attained legal custody of my children from state custody. I have a girlfriend who spent 20+ years in Jail for a murder robbery charge back in 1991. She has done her time and we would like to move forward and living together and possible marriage. My ex lost the kids through drug offenses and knows of her and says sdhe will not allow me to have my kids around her. I have legal custody and she does not but still has parental rights . Can she have thew kids removed from my custody

Anything's possible, but it's not likely.

So your ex would claim that a woman who committed a violent felony some 20 years ago would be a danger to your children? Doesn't look that persuasive to me.

When you say your ex "still has parental rights", basically you mean that she still has parental obligations, specifically the obligation to pay child support, correct?