I think it is a very bad idea to create a distinction between prisoners and "real people." People in prison are still humans, still citizens of this country, and still entitled to their rights as human beings. Certain rights are restricted only through due process and trial by jury and all that, but being convicted of a crime does not make you a Slave.
Some people on the Escapist seem to have a rather vindictive attitude towards criminals, and I imagine that when this thread gets more posts some of them will show up. But often times these people only think of murderers and rapists when they think of "criminals." There are quite a few ways to end up in prison, many of them extremely unjust and unfortunate, and to apply the right of the government to conduct medical tests on them is way too close to Nazi Germany for my comfort.
To give an example of how perverted this can get, let's consider another instance where criminals are stripped of their rights: in many states, convicted felons lose the right to vote. Permanently. If you are convicted of a felony, you can never vote again. A lot of people would probably be all for this. Until you realize that in some of those states Destruction of Property becomes a felony once you do more than $250 worth of damage. In other states, shoplifting $100 worth of stuff is a felony. This means that you could permanently lose your right to vote for breaking your buddy's laptop or shoplifting an iPod.
Or take the War on Drugs, the single biggest imprisoner of normal, harmless people. Now, everybody knows that Prosecutors use plea bargins a lot--that is, they offer to reduce charges against people, or even grant them complete immunity, in exchange for their cooperation and for "naming names." There are many cases in the War on Drugs where the DEA has busted a few people in a minor pot dealing ring--harmless, nonviolent people--and then plea bargained with them to place the blame entirely on one poor sap. So if there were 20 people in the ring, and each person had a pound of pot, they would plea bargain to place all of the pot in one person's possession--that would put them over a certain threshold, which would allow the DEA to prosecute for a higher crime and therefore be able to go to the news and report that they had caught a drug kingpin and really served some justice. But lost in there is the fact that one poor idiot with no more pot than anyone else is now in hardcore prison, probably for decades (now, I'm unsure about the amounts here and how they correspond to the actual law, but I think the point stands).
The point is, the law is an imperfect institution, and its failures to deliver justice are many. Why would anybody want to INCREASE the stakes by giving one court the power to turn a human being into a Dr. Mangele victim?