Maybe go for a HCA in an acute mental health ward or PICU - I think it would look good. Shows you can tolerate high stress situations with dramatic presentations. Then you could build up for when a low or medium secure ward post is available. Also, don't forget the forensic clients are everywhere
I have been about and on many jobs I have encountered a client with a forensic history - even in primary care!
Support worker in addictions as well. Found a higher forensic history in this client group.