Updated

President Obama on Thursday commuted the sentences of 330 federal inmates convicted of drug offenses.

The final batch of commutations came on the eve of Donald Trump’s inauguration and caps off an extraordinarily long list of people who have had time shaved off their sentences courtesy of the outgoing president.

Over the past 30 years, tens of thousands of mostly black and Hispanic men were arrested in a sweeping effort to combat drug-related crimes. Many were sentenced under strict federal guidelines that had them behind bars for decades.

During his eight years in the White House, Obama repeatedly – but unsuccessfully - called on Congress to pass a sweeping reform to the criminal justice code.

“With this last act of mercy, President Obama has closed out a historic effort to restore some balance and fairness to a federal prison system that has caused needless destruction of thousands of lives and families,” Jessica Jackson Sloan, national director of the #cut50 initiative, said in a written statement. “We continue to waste our precious resources to lock up people who have committed drug-related crimes that do not warrant decades, and certainly not life, in prison.”

Unlike pardons, which erase legal liabilities from a conviction, commutations typically shorten the sentences of prisoners but do not wipe their record clean.

In all, Obama has granted clemency to 1,715 prisoners, more than any other person in U.S. history. He has also denied more clemency requests than the past 13 presidents combined.