It might seem better to accept the rapid advances in drugs and technology.
If women can have three year contraceptive implants, why not let violent people including criminals or mental patients take their vital behaviour-modification medication by implant? Old, male, lawmakers tended to cringe at the idea of what they called "chemical castration". But there are it appears medicines available or able to be developed which can curb most appetites. If the side effect is to cause apathy, that would seem better for the patient/criminal.
The ideal, it would seem, would be to have a mental patient/ or criminal who had low testosterone, low interest in anything, low inclination to anger, and could scarcely if at all be bothered to turn round and look even if there was a view of a child/ chocolate cake/ cup final recording/ vulnerable woman/ bottle of alcohol/ supply of drugs/ perceived 'enemy'.
And, instead of tags which can be cut off, why not implant trackers?
Instead of hopeless, unaffordable attempts by probation officers to discover what people are up to, who they see, where they go and what street drugs or alcohol they consume, why not an implanted blood monitor, triggering an alert to the nearest police car?
And instead of caging in prisons, for a thousand pounds a week, why not use house arrest, monitored by A.I.? It would surely be both far cheaper and far more thorough than prison, which currently introduces people to drugs even if they were not previous users, while also acting as a university of crime, plus validating and reinforcing any behaviour, by meeting others who have done the same.
With house arrest, which could be carried on for life, subject to review by doctors and courts, there could presumably be control of what the occupant can access for entertainment, so there should be no available porn to inflame unhealthy wishes. In fact, whatever is known to rouse violence can be excluded.