WASHINGTON - Rep. Keith Ellison, the first African American elected to the U.S. House from Minnesota, made headlines around the world five years ago as the first Muslim in Congress. Since then, he has been seen less as a black spokesman than an advocate for American Muslims.

That changed Tuesday when Ellison, a former criminal defense attorney and grandson of a Louisiana civil rights activist, provided firsthand testimony on racial profiling before a Senate panel on civil rights.

"Racial stereotyping is simply not good policing," Ellison told the Senate Judiciary Committee. "It threatens the values Americans hold dear."

The Minneapolis Democrat is a co-sponsor of the End Racial Profiling Act, which seeks to change a range of police practices, including tightening Bush-era guidelines on racial profiling and extending them to national security and border security investigations.

Since it was filed in December, the little-known bill has barely advanced in either the Democratic-led Senate or the Republican-led House.

Police groups oppose it, arguing that racist police tactics already are banned under the Constitution and are hardly the norm in modern law enforcement.

Some police officials say legislation that treats racial profiling as a pervasive problem only heightens tensions between police and minority communities.

But now, the NAACP and other civil rights groups are giving the bill a new impetus, galvanized by the national uproar over the death of Trayvon Martin, a black teenager who was killed in February by a civilian neighborhood watch volunteer in a gated community in Sanford, Fla.

The shooter, George Zimmerman, told police he thought the young man in the hooded sweat shirt looked suspicious.

Zimmerman has said he acted in self-defense, but the case has raised questions about a possible racial motive and led to criminal charges last week against Zimmerman.

'I believe I've been stopped'

Ellison did not mention Martin by name or detail any police encounters of his own during his testimony.

But in an interview afterward, he acknowledged that he experienced what he considered racial profiling growing up in Detroit and during his college years in Minnesota and Washington.

"I believe I've been stopped for illegal reasons," Ellison said. "But I was taught as a kid to put your hands firmly on the steering wheel, don't say anything they could take offense to, pass the 'attitude test.'"

The hearing on racial profiling -- reportedly the first in the Senate in a decade -- was billed as a way to highlight not just the Martin case, but "the different forms of racial profiling," including state immigration laws in Alabama and Arizona that critics say subject Hispanics to heightened scrutiny.

Ellison also sought to focus the hearing on what he called discriminatory law enforcement not just against racial minorities, but against American Muslims.

"Like other Americans, Muslim Americans want law enforcement to uphold public safety, and not be viewed as a threat but as an ally," Ellison said.

Ellison said the times he believed he was racially profiled "caused me anxiety, fear -- it was humiliating and insulting. I think the officers intended to humiliate me, and I got the impression that the real aim was to just sort of let me know that I wasn't as free to roam the streets as anybody else."

Not so clear cut, police say

But police officers say that in most traffic stops it's difficult to tell a person's race until they pull over.

Frank Gale, a captain in the Denver County Sheriff's Department and a top official in the Fraternal Order of Police, the nation's largest police union, testified against Ellison's bill.

Gale, who is black, blamed the furor over racial profiling on "hype" by politicians, the media and "others with political agendas."

He said that race can be a factor in sophisticated criminal profiling, including the Unabomber case, where psychological data suggested the suspect was white.

But the focus on illegal racial profiling, he said, contributes to "a mistaken perception on the part of some that the ugliness of racism is part of the culture of law enforcement."

"It's pretty hard to call it racial profiling if you can't even tell the gender of who it is you're stopping," said consultant Mike Quinn, a retired Minneapolis police sergeant who wrote "Walking With the Devil: The Police Code of Silence." "But I do know it does happen."

Ellison and his backers acknowledge that the majority of police officers are professional.

"What most officers don't realize," Ellison said, "is it only takes one person in a blue uniform to act out before people say 'the police' did this to me."

Kevin Diaz is a correspondent in the Star Tribune Washington Bureau.