The U.S. Supreme Court heard arguments this morning about Arizona’s controversial anti illegal immigration law.

A crowd of SB 1070 opponents outside the U.S. Supreme Court on Wednesday. (Photo by Victoria Pelham - Cronkite News Service)

A supporter of SB 1070 outside the U.S. Supreme Court on Wednesday. (Photo by Salvador Rodriguez - Cronkite News Service)

SB 1070 requires local police to check on the immigration status of people stopped or detained if they suspect the person is in the country illegally.

Arizona reporter Terry Greene Sterling is a contributor for the Daily Beast website and author of Illegal: Life and Death in Arizona’s Immigration War Zone. She was in court Wednesday and says the justices focused on that issue.

Greene Sterling said there were about 400 protestors who opposed SB 1070 outside the court.  Governor Jan Brewer and the bill’s sponsor, former state Senate President Russell Pearce, were also on hand.

Listen to the full interview with Greene Sterling.

Read the transcript of Wednesday's arguments.

Listen to analysis of the proceedings from Wednesday's Here and Now with Steve Goldstein.

Updated 4/25/2012 at 3:09 p.m.

EDITOR'S NOTE (4/28/2012): An earlier version of this story misspelled the name of Terry Greene Sterling.