If we are going to use animals then we should at least use the humans in prison that act like animals. Why should something that has done nothing wrong be subjected to experimentation? People in prisons in our country have been found guilty of a crime like murder, assault, and rape. I think that people who with no doubt committed murder should no longer have a say and have that be how they contribute something back to society. They had rights when they were not committing crimes and knowingly killing and raping people. If they want rights they shouldve thought about that before taking away someone else.Ever since the Nuremburg war trials again Nazi doctors, experiments on humans without their consent has been considered a war crime. This has been adapted by most countries, including the US, as a part of law. If you want to experiment on prisoners, you need to explain how it can possibly be consensual.
You might think that US prisons are different than prisoner of war camps, because the people there are guilty of things like murder, assult and rape. But this is not what is going on in most prisons. In 2006, 49.3% of state prisoners were in jail for nonviolent offenses. For federal prisons, that number is 90.7%. (See wikipedia, end of the fourth paragraph down.) The drug war is largely responsible for this. In 2004, the majority of (55%) prisoners in federal prison were there for drug offenses. The same year in state prisons, 22% of the prisoners were there for drug offenses. (See here.) For profit prisons also play a role here, because they lobby for tougher sentencing laws to increase their business, and hence their profit. (See here and here. In the most extreme case, a for builder of for-profit juvenile detention facilities in Pennsylvania bribed two federal judges to send innocent kids to their juvenile prisons. The judges in the case received 28 and 17 years in prison. The developers of the prisons who paid the bribes received 18 months and 12 to 18 monts.
You said, "They had rights when they were not committing crimes and knowingly killing and raping people. If they want rights they shouldve thought about that before taking away someone else." But most rights specified in the US consitition do not go away if you have committed a crime. In fact, many of them only make sense after a person has been accused of a crime. The right to a fair trial, the right to see the evidence presented against you and the right to be free of cruel and unusual punishment are all rights that you get after you enter the justice system.
It is also worth looking at what happens when people do experiment on prisoners. The most notorious cases of this are the Nazi war crimes, but this has happened in US prisons as well. In 1906 Dr Richard P Strong began experiments infecting prisoners in the Phillipenes, which was then a US possession, with cholera. Thirteen prisoners died when they were accidentally infected with bubonic plague. Six years later strong conducted lethal experiments where prisoners were infected with beriberi. The surviving prisoners were given cigars as compensation. For more information, see this article, called "They were cheap and available" on the history of experimentation on prisoners. The article was originally published in the British Medical Journal, but the full article was posted on a web page run by health case activists.