Why hasn't Obama pardoned way more people?

President Obama commuted the sentences of 46 nonviolent drug offenders today, including 14 who had been sentenced to life in prison.

It was a long-awaited move for a president who before this year used the presidential pardon power in fewer cases than any of his predecessors. “He’s been unusually stingy—he’s a clemency Grinch,” Douglas Berman, an Ohio State law professor, told Yahoo News today.

Obama’s move on Monday more than doubled, to 89, the amount of people that he has given commutations. In the first six years of his presidency, Obama granted fewer pardons and commutations than his predecessors. As Yahoo reported, before this year, he had granted fewer pardons than any president since James Garfield, who was assassinated in 1881 after only six months in the White House.

Since then he’s stepped it up—as of today, he’s granted more commutations than George W. Bush, Clinton, George H.W. Bush and Ronald Reagan combined. (Pardons generally apply to people after they are released from prison, while commutations end someone’s prison time while they’re currently behind bars.)

“These men and women were not hardened criminals,” Obama said in a Facebook video announcing today’s commutations. “But the overwhelming majority had to be sentenced to at least 20 years, and 14 had been sentenced to life.”

“I believe that at its heart, America’s a nation of second chances. And I believe these folks deserve their second chance,” he said.

Part of the reason Obama has granted fewer pardons and commutations stems from administrative upheaval in the White House pardon office, which reviews all requests. Ronald L. Rodgers, the George W. Bush-appointed head of the office, resigned last year after Obama complained that he wasn’t receiving a representative sample of pardons

“I noticed that what I was getting was mostly small-time crimes from very long ago,” Obama told the Huffington Post in March. “It’d be a 65-year-old who wanted a pardon to get his gun rights back. Most of them were legitimate, but they didn’t address the broader issues that we face, particularly around nonviolent drug offenses.”

After appointing a new head of the office and announcing an initiative to consider more nonviolent drug cases, the administration suggested last year that it might grant commutations to hundreds or even thousands of low-level offenders. Since then, the tiny pardon office (with a staff of seven lawyers) has been swamped with more than 35,000 applications. That means that more than 16% of the federal prison population has applied for clemency.

Generally, presidential pardons and commutations are symbolic or individual actions. The 46 people who received commutations today barely make a drop in the bucket of the 208,000 inmates currently housed in the federal prison system. But executive clemency doesn’t have to be used that way: In 1977, on his second day in office, Jimmy Carter pardoned all Vietnam draft-dodgers.

And while Obama has rewritten sentencing guidelines to reduce mandatory minimums, those reforms only apply to criminals going forward. He could use pardons and commutations to, in effect, retroactively extend the sentencing changes his administration made to prisoners sentenced decades ago.

Notably, 42 of the 46 people whose sentences he commuted were convicted on cocaine charges. The Fair Sentencing Act, which Obama signed into law in 2010, greatly reduced cocaine mandatory minimums and reduced the gap between sentences for different types of cocaine. All of today’s commutees were sentenced between 1990 and 2007.

“This is really the only way we have to go back and fix injustices in the past,” Amos Irwin, the chief of staff at the Criminal Justice Policy Foundation, told Fusion. “That’s the sort of mass action that we need to take here, because everyone agrees that these sentences are unjust.”

“There’s been such concern over not being soft on crime that no [recent President] has really used their pardon power in any kind of widespread way,” Irwin said. “Obama can quickly eclipse what previous Presidents have done: A short time ago, he had pardoned fewer people than anyone else, but now he’s quickly passing the others.”

By extending presidential clemency more broadly to a large proportion of low-level nonviolent drug offenders, Obama could also reverse the racial bias that has plagued presidential pardons for generations. A ProPublica investigation found that white petitioners in George W. Bush years were four times more likely to receive a presidential pardon or commutation than petitioners of color. All but 13 of the 189 people Bush pardoned were white.

Ultimately, the presidential pardon power could be a powerful tool to help Obama accomplish his criminal justice reform goals—but only, advocates say, if the number of people he pardons is measured in the thousands, not the dozens. He’ll have more opportunities to highlight his criminal justice reforms this week, as he speaks at the NAACP’s annual conference tomorrow and becomes the first sitting president to visit a federal prison on Thursday.