If he was never put on trial and never found guilty the current administration could bring an indictment and put him on trial for murder.
I don’t know what the status is about a State case. Considering how the current Administration feels about Border Patrol agents...
He was never convicted of murder, though he should have been. There was a lot of jurisdictional dancing between the state and federal courts, and ultimately the government protects its assasins.
We learned during the Clinton administration that it is perfectly legal for the government to kill anyone they desire, and there isn't a damned thing we can do about it.