WASHINGTON (Reuters) - U.S. President Donald Trump on Friday granted a pardon to controversial former Arizona lawman and political ally Joe Arpaio less than a month after he was convicted of criminal contempt in a case involving racial profiling.

“Throughout his time as sheriff, Arpaio continued his life’s work of protecting the public from the scourges of crime and illegal immigration,” said a White House statement announcing Arpaio’s pardon, the first of Trump’s administration.

Arpaio, 85, the self-proclaimed “toughest sheriff in America” lost a bid for re-election in Arizona’s Maricopa County in November after 24 years in office.

He is known for his crackdown on undocumented immigrants and investigating unfounded Trump-supported claims questioning former President Barack Obama’s citizenship.

“I have to thank the president for what he has done, that’s for sure,” Arpaio told Reuters in a brief telephone interview from his Arizona home. “He’s a big supporter of law enforcement.”

Arpaio said his lawyer was sent a copy of the pardon on Friday afternoon and he planned a press conference to discuss what he said were new details in the case. He declined to say if he would run again for sheriff.

“I’m not going away,” added Arpaio.

Arpaio told Reuters that he would reveal more about the case on Monday or Tuesday and detail the “real story” behind the case that brought him to trial. He has long maintained that the prosecution by the administration under President Barack Obama was political, aimed at helping oust him from office.

He said his attorney delivered the good news the same day as his wife’s birthday, adding “he came over to give my wife a birthday gift and it was a pretty good one,” said Arpaio, alluding to the pardon, as he was about to leave for her celebration dinner.

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Civil rights advocates slammed Trump’s decision as an endorsement of racist and unlawful immigration policies.

“Once again, the president has acted in support of illegal, failed immigration enforcement practices that target people of color and that have been struck down by the courts,” said American Civil Liberties Union Deputy Legal Director Cecillia Wang, who sought the court injunction against Arpaio.

The pardon sent “a dangerous message that a law enforcement officer who abused his position of power and defied a court order can simply be excused by a president who himself clearly does not respect the law”, Vanita Gupta, president of the Leadership Conference on Civil and Human Rights and former head of the U.S. Justice Department’s civil rights division, said in a statement.

Alejandra Gomez, co-executive director of Living United for Change in Arizona (LUCHA), said: “President Trump pardoned a terrorist tonight. Joe Arpaio intentionally terrorized immigrant communities across Arizona for decades and traumatized an entire generation of Arizonans...

“The only proper place for him is in a jail cell,”

Gomez said in a statement.

Democratic Senator Patrick Leahy said it was “disheartening that he set the bar so very low for his first pardon... The ex-sheriff is a self-aggrandizing braggart who promoted racist law enforcement practices and cost taxpayers millions, and that is a reason they did not reelect him.

“After the racism and hate in Charlottesville, our country needs to come together and heal. But that healing will not come from a president who only exploits divisions and fears,” Leahy said in a statement.

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Arpaio, who campaigned for Trump in 2016, was convicted on July 31 by U.S. District Judge Susan Bolton, who ruled he had willfully violated a 2011 injunction barring his officers from stopping and detaining Latino motorists solely on suspicion that they were in the country illegally.

Arpaio admitted to inadvertently disobeying the court order but said his behavior did not meet a criminal standard. He said the prosecution was a politically motivated attempt by the Obama administration to undermine his re-election bid.

Arpaio had been scheduled to be sentenced on Oct. 5 and faced a fine and maximum sentence of six months in jail.

His controversial tenure as sheriff brought Arpaio national headlines for massive roundups of suspected illegal immigrants and for the way he ran the Maricopa County jail.

He reinstated chain gangs, made inmates wear uniforms that were pink or old-fashioned black and white stripes and forbade them coffee, salt and pepper.

Critics said as sheriff Arpaio spent too much time courting publicity and not enough on basic policing. The East Valley Times newspaper won a Pulitzer Prize for a 2009 series showing that arrests in the county had dropped while many violent crimes were not investigated and response call times had increased.