The Supreme Court just handed down a 5-4 ruling, declaring that Guantanamo Prisoners have the right to challenge their detention in US Courts. According to the SCOTUSblog:

In a stunning blow to the Bush Administration in its war-on-terrorism policies, the Supreme Court ruled Thursday that foreign nationals held at Guantanamo Bay have a right to pursue habeas challenges to their detention. The Court, dividing 5-4, ruled that Congress had not validly taken away habeas rights. If Congress wishes to suspend habeas, it must do so only as the Constitution allows - when the country faces rebellion or invasion.
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The Court also declared that detainees do not have to go through the special civilian court review process that Congress created in 2005, since that is not an adequate substitute for habeas rights. The Court refused to interpret the Detainee Treatment Act - as the Bush Administration had suggested - to include enough legal protection to make it an adequate replacement for habeas. Congress, it concluded, unconstitutionally suspended the writ in enacting that Act.

You can read more about this decision at the ACLU Blog of Rights.

Update: You can download the decision in Boumediene v. Bush from SCOTUSblog.

You can join the fight to close Guantanamo once and for al, and represent all detained therel at the ACLU website.