The Supreme Court is letting stand a lower court's ruling barring Florida from enforcing a contentious immigration law that imposes criminal penalties against undocumented migrants who enter the state.

The Supreme Court on Wednesday refused to revive an aggressive Florida immigration law that had been blocked by lower courts.

A federal judge has blocked a key part of a new law that imposed additional restrictions on the state’s ballot initiative process, saying a ban on non-Florida residents and non-U.S. citizens collecti...