They might not be guards but surely they (or rather the organisation they work for) is still potentially liable here. If he’s escaped the facility or two people looking after him when outside given they know he’s violent and a danger then that, even with limited info, does seem to indicate some negligence regardless of any overall issues with funding or the mental heath system in general.
If he was in the community and there wasn’t sufficient funding to adequately monitor him and others like him etc... then sure perhaps more blame on the government too. However it sounds like this guy was a clear danger and already supposed to be watched closely.
Again, these facilities they are housed are literally just 2 up 2 down houses. There is no process in place to have them locked up and under 24 hour watch unless they have actually committed a crime, by which they'll be sent to a psychiatric detention centre. It's basically live in care rather than detention.
it's possible he was under section and on supervised day release. But my experience is that this is rare.
In a majority of cases the carers won't even have any power to detain the person if they run off and have to resort to reporting them to police as a missing person.
It's a similar situation in the larger children's homes housing problem kids. Unless they are under some kind of section the doors aren't locked and they come and go as they please.
I once had to review a case of a schizophrenic who murdered his mother to assess if the local mental health services were negligent. I was shocked at how laissez faire the mental health workers were with somebody who was very vocal about not wanting to take his medication, openly expressed fantasies of murder and was solo living in the community.
The response I got to from the trust, when I asked why on earth he hasn't been sectioned, was "it's not against the law to be mad and he hadn't done anything like this before"