Trump pardons Alice Johnson, who praised him at Republican convention night before

President Donald Trump on Friday issued a full pardon for Alice Johnson, a day after her speech aired at the Republican National Convention.

Johnson, a criminal justice reform activist whom he had granted clemency two years before, has been heavily featured by the president's re-election campaign. She had served 21 years of a life sentence for for a first-time, nonviolent offence connected to a role she played in a cocaine distribution ring.

The 65-year-old first came to the president's attention thanks to the celebrity advocacy of reality TV star Kim Kardashian West before he commuted Johnson's sentence in June 2018. Kardashian West visited the White House to make a personal appeal to the president for Johsnon's release.

Just before signing the pardon in the Oval Office Friday, Trump mentioned her attendance at his party's political convention the night before, when he accepted the GOP nomination for president.

"We are giving Alice a full pardon," Trump said. "I just told her. We didn't even discuss it. We just -- you were out there, I saw you in the audience last night, and I asked the folks if you could bring Alice over. We're going to give a full pardon. We're going to do it right now."

The night before, in a speech that aired at the GOP convention, Johnson had praised Trump and thanked him for commuting her sentence. She attended the president's Thursday night acceptance speech in person on the grounds of the White House.

By issuing a full pardon to Johnson after she demonstrated loyalty to the president, Trump continued a trend of using his clemency power to show favor to those who have shown loyalty to him.

Last month, the president commuted the sentence of his former campaign adviser Roger Stone, who was found guilty of obstructing a congressional investigation and witness tampering. Investigators hoped Stone would say whether the president obstructed justice or lied under oath, but he never turned on the president.

Trump awarded his first presidential pardon to the controversial former sheriff of the metro Phoenix area, Joe Arpaio, who was convicted on charges of defying a judge's order to stop detaining people based on suspicion of their immigration status. Arpaio had endorsed the president in 2016.

The president also hasn't ruled out pardons for Michael Flynn, his former national security adviser, and Paul Manafort, his former campaign chairman.

In Johnson, the president's campaign has found a criminal justice reform advocate who has become a centerpiece of his efforts to court Black voters, which included in a multimillion-dollar Super Bowl advertisement that ran earlier this year.

Since she was freed, Johnson has called for the release of others she sees as serving unfairly harsh prison sentences.

Shortly before Trump commuted Johnson's sentence in 2018, Kardashian West had expressed optimism following a meeting with the president. She said in an interview with Mic that the president "really understood, and I am very hopeful that this will turn out really positively."

Days later, the president commuted Johnson's sentence.

ABC News' Will Steakin contributed reporting.