Washington (CNN) -President Barack Obama commuted the prison sentences of 46 drug offenders, saying in a video posted online Monday that the men and women were not "hardened criminals" and their punishments didn't match the crimes they committed.
Obama said the move was part of his larger attempt to reform the criminal justice system, including reviewing sentencing laws and reducing punishments for non-violent crimes. With Monday's announcement, Obama has commuted more sentences than any president since Lyndon B. Johnson.
"I believe that at its heart, America is a nation of second chances, and I believe these folks deserve their second chance," Obama said in the video.
The move brings the number of Obama's commutations to nearly 90. Most of those have been for federal prisoners incarcerated for drug offenses who were slapped with long sentences mandated under guidelines set during a drug-and-crime wave in the 1980s. Under current sentencing guidelines most of those prisoners would have already finished serving time.
Of the 46 prisoners whose sentences were commuted on Monday, 13 were sentenced to prison for life.
The new round of commutations comes after 22 prisoners convicted of drug crimes were granted release earlier this year. In late 2014, eight criminals were granted commutations.
Unlike a presidential pardon, a commutation does not erase a criminal conviction, only reduces a sentence. In his presidency Obama has granted 64 pardons.
The White House on Monday posted a letter Obama wrote to each of the 46 men and women whose sentences were commuted.
"I am granting your application because you have demonstrated the potential to turn your life around," Obama wrote. "Now it is up to you to make the most of this opportunity. It will not be easy, and you will confront many who doubt people with criminal records can change. Perhaps even you are unsure of how you will adjust to your new circumstances. But remember that you have the capacity to make good choices."
Later this week, Obama is expected to discuss his plans for criminal justice reform further. He travels Tuesday to Philadelphia to speak at the annual convention of the NAACP, and on Thursday will become the first president to visit a federal prison when he tours the El Reno facility in Oklahoma.
While there, he's expected to cite bipartisan calls for chances to the criminal justice system that would reduce overcrowding in prisons and create a system where sentences better match the crimes they are meant to punish. The effort to reform the system has gained support from Republicans like Sen. Rand Paul, the libertarian-minded presidential candidate, and David and Charles Koch, the industrialist brothers who have spent millions on conservative causes.
"Over the last few years a lot of people have become aware of the inequities in the criminal justice system," Obama said in the video. "Right now, with our overall crime rate and incarceration rate both falling, we're at a moment when some good people in both parties, Republicans and Democrats and folks all across the country, are coming up with ideas to make the system work smarter and better."