The Justice Department has set up a hotline for the public to report potential civil rights concerns regarding the Arizona law that requires police to check the immigration status of those they stop for other reasons.

The hotline phone number is 1-855-353-1010. The email is: SB1070(at)usdoj.gov.

The Supreme Court unanimously approved Arizona's "show-me-your-papers" requirement on Monday but struck down provisions that created state crimes allowing local police to arrest people for federal immigration violations.

In his majority opinion, Justice Anthony Kennedy also said the law could - and suggested it should - be read to avoid concerns that status checks could lead to prolonged detention.

He said detaining individuals solely to verify their immigration status would raise constitutional concerns. But he did not define what would constitute excessive detention.