Transcript for Backlash over Trump's pardon of Arpaio

Back now with the political fire storm over president trump's pardon of former sheriff, Joe arpaio. The president announcing the move in a tweet just as that hurricane Harvey was bearing down on the country. Here's ABC's Mary Bruce. Reporter: As hurricane Harvey was hitting Texas, the president getting briefed, but also at the center of a political storm of his own making. First Friday evening, signing that directive, implementing his ban on transgender individuals from serving in the military. Then hours later with little fanfare, the president pardened controversial former Arizona sheriff, Joe arpaio. The 85-year-old was convicted with critical contempt for ignoring a judge's order to stop using racial profiling to detain Latinos. He hadn't even been sentenced yet. I have fought on the front lines to prevent illegal immigration. Reporter: But critics accuse him of blatant discrimination. Immigration advocates and human rights groups reacted swiftly. I'm angry. What trump did today was part in racism, white supremacy and okayed the terror that arpaio caused. Reporter: In a statement, the white house praised arpaio's admirable service to the nation. Arizona Republican John McCain says the president's pardon undermines his claim for the respect of rule of law, adding that arpaio has shown no remorse. On Twitter, arpaio thanked the president for, "Seeing my conviction for what it is, a political witch hunt." Tonight, the timing of the president's move is raising eyebrows. Senate democratic leader, chuck Schumer is accusing him of using the cover of hurricane Harvey to avoid scrutiny, tweeting, so sad, so weak. And tierngonight, there has been yet another departure from the administration. Counterterrorism correspondent, Sebastian Gorka. He has been a defender of the president's, but his role has been unclear. He says he planned to resign, but administration sources tell us he was forced out. Tom. It was a busy Friday night at the white house.

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