First, please do NOT worry about your preference as a condition for your parenting skills. There are LOTS of social studies now available that stand for the scientific position that healthy happy GLBT parents raise healthy happy children as often as do healthy happy heterosexual couples. The issue in this case is your child, his welfare and rights are much more important to any judge than your rights or those of his father. The fact that there is violence in the father's past is a critical component of what a judge is likely to do with the custody issue and so you need to be sure that you have proof of his incarceration, the prior orders and the threats to you, your partner and your child. It is not true that "his past is wiped clean" and a judge will care much about the current threats of kidnapping than his claim to have served his time and therefore have a "clean slate." So, here's what I would recommend: go first to the District Attorney and see if they will file a Protective Order for you because of the current threat to your child. If they cannot or will not, you need to find a quality lawyer who is accustomed to GLBT people and understands parenting issues. That lawyer should help you with a Suit Affecting Parent Child Relationship, setting out strong protection for your son. IF your son's father has access to him, it should be supervised, and there should be lots of therapeutic hands and eyes on him to be sure that he is safe through this process. I would also encourage you to seek a qualified therapist, not just for you and your partner, but for your son as well. He is likely to sense your anxiety and may have some questions about his biological father that might be otherwise hard to answer. A therapist can help you sort through these worries.
You should have noticed that since he did past time for attempted murder, he had the propensity for violence. The important thing is the best interest of the child. That being said, the court should allow a social study to be conducted to see wether either parent is fit for having a child.
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