Fifteen years after Cesar Chavez’s death, the federal government is recognizing the legacy of the late civil-rights leader.

President Bush this month signed a bill to commemorate the vital role Chavez played in the struggle for better wages and working conditions for farm workers.

The Cesar Estrada Chavez Study Act directs the Interior Department to research sites important in Chavez’s life for possible inclusion in the National Parks System.

The department will consult Chavez’s relatives and representatives of the farm-worker movement to decide whether any of the sites should be national historic landmarks.

"Cesar Chavez serves as a labor and Latino hero and an example for all Americans, showing that one person’s life can make a difference," Sen. Barbara Boxer said in a statement.

The law, signed May 8, was part of a larger package that dealt with various public land and national parks issues.

State and local governments have taken the lead in honoring Chavez, who co-founded the union that became known as the United Farm Workers.

He became famous in the 1960s for organizing strikes, marches and boycotts to draw attention to poorly paid farm workers in squalid conditions.

His birthday, March 31, is a state holiday in California.

Parks, schools and streets have been named after him throughout the state. A park in Colton and a middle school in San Bernardino bear his name.

Rep. Joe Baca, D-San Bernardino, has introduced legislation to make Chavez’s birthday a national holiday.

"Cesar was not only a champion for workers’ rights and human dignity, but also a strong advocate for the environment," Baca said in a statement. "Our National Parks system is a fitting vehicle to recognize his importance."

Baca said that Chavez’s close ties to Arizona, his birthplace, and California, home to some of his most significant labor victories, seem like good places for national commemorative sites.

Lynda Gonzalez, 46, of Bloomington, said Chavez was a positive example of peaceful activism for all people, regardless of race or nationality.

Gonzalez traveled to Central California in 2004 for the opening of a visitors center and memorial garden at Chavez’s burial place.

"To me, Cesar Chavez represented hope," Gonzalez said. "There should be more places named after him. He worked so hard to achieve what he achieved."