If this person does have GID, wouldn't one consider withholding 'medically necessary' treatment while someone is incarcerated to be 'Cruel and Unusual punishment?'
Would it be ok to withhold HIV drugs from a gay inmate because they could be seen as giving gay men a bad name?
Would withholding GID treatment from the inmate imply that such treatment is not medically necessary, and how would that affect us.
No. When your liberty is taken from you the government assumes a lot of obligations according to our legal systems. Among those are a person's well being and that includes medical care. However that does not mean if a person has rotten teeth the state has to provide dental implants (as an example). It does mean that medical care must be provided for treatable lie threatening conditions. However if the threat is on of suicide then the treatment is isolation and 24 hour observance.
In the arena of GID or alleged GID the judicial decisions are just now being written and it will be quite a few years before the courts work their way to clearly defined rules. Typically that will lag behind what the medical community applies as standards in general society.
One important fact to remember is that incarceration expenses are borne by the taxpayers. Inmates with incurable conditions are often released by the system to live out their last few years or to avoid extremely high costs. In the case of murder, however, release for medical conditions is extremely rare.
In answer to one of your questions nothing decided in an incarceration situation will affect us. Jail decisions follow rather than lead the justice system.