Is It Unconstitutional for States to Imprison Undocumented Immigrants? Justice Anthony Kennedy argues that a recent state law making it a crime to be an undocumented immigrant in Arizona impinges on the U.S. federal government's authority to regulate immigration. Justice Antonin Scalia argues that it is not unconstitutional for a state to supplement U.S. federal immigration law with its own, harsher penalties for illegal immigration.
