By MARY CLARE JALONICK, Associated Press

WASHINGTON (AP) — Racially motivated, civil rights-era killings that are now cold cases will get fresh looks under legislation signed by President Barack Obama.

Obama signed the bill Friday. It indefinitely extends a 2007 law that calls for a full accounting of race-based deaths, many of which had been closed for decades. The law was set to expire next year.

The bill is named after Emmett Till, a 14-year-old black boy killed in 1955 after whistling at a white woman. His killers were acquitted of murder but later admitted their crimes to a reporter and couldn't be retried.

Many other similar cases were poorly investigated and prosecutions were rare.

The law provides federal resources to local jurisdictions to look into the cases and extends the time span of cases to be considered to December 31, 1979. It will also require the Justice Department and the FBI to consult with civil rights organizations, universities and others who had been gathering evidence on the deaths.

There has so far been one conviction as more than 100 cases from the 1960s and earlier have been reviewed. New racially suspicious deaths have been identified for investigation.

North Carolina GOP Sen. Richard Burr and Missouri Democrat Claire McCaskill sponsored the bill in the Senate. In the House, the bill was negotiated by civil rights icon John Lewis, D-Ga.; John Conyers, D-Mich., the top Democrat on the House Judiciary Committee; and Republican Rep. Jim Sensenbrenner of Wisconsin.