
Madison M. answered 06/24/19
CJ Major and Researcher with the Midwest Innocence Project
Typically illegal immigrants have certain rights based on their situation and presidential administration's policies. In the United States, this could vary monthly. The United Nations and other international organizations such as the European Union have guidelines for seeking asylum. Although the United States might not be a part of these organizations, international law can still be binding should an illegal immigrant decide to sue and win in the International Criminal Court.
Examples of variance of rights could include: if the illegal immigrant is a skilled worker, if the illegal immigrant was at one point a legal immigrant that failed to update their visa, if the illegal immigrant is of a protected class that is being persecuted in their home country, if the illegal immigrant has a Sate and files proving their home nation (some nations dissolve and so that is when this becomes an issue with lost birth certificates, files etc.), if the illegal immigrant has family sponsors in the said foreign State.
Illegal immigrants are not prisoners of war yet, detainment of them needs to follow international law norms and law like the Geneva conventions or even the Declaration of Human Rights. The prisoner rights from these bodies of law are actually more strict than the United States Eighth Amendment against cruel and unusual punishment. For example, it is still legal in the United States to allow for force feeding prisoners who go on hunger strikes, yet, in Guantanamo Bay prison, the United States cannot punish prisoners in such a way after a high profile suit and it being located outside of the United States. Typically nations like the United States and Great Britain have agreements on extradition of illegal immigrants to carry out sentences (should the immigrant commit a crime) elsewhere due to Great Britain's ban on the death penalty and the United States' use of such punishment. United States and other nations have agreements on detainment of those from a foreign nation.
Short answer: they do but they vary based on circumstance