In a video released by the White House on Monday, President Obama commuted the sentences of 46 federal prisoners, the majority of whom were nonviolent drug offenders.  WASHINGTON — President Obama announced on Monday that he was commuting the sentences of 46 federal drug offenders, more than doubling the number of nonviolent criminals to whom he has granted clemency since taking office.  “These men and women were not hardened criminals, but the overwhelming majority had been sentenced to at least 20 years; 14 of them had been sentenced to life for nonviolent drug offenses, so their punishments didn’t fit the crime,” Mr. Obama said in a video released on the White House Facebook page, in which he is shown signing the commutation letters. “I believe that at its heart, America is a nation of second chances, and I believe these folks deserve their second chance.”  Mr. Obama’s action on Monday brought the total number of commutations he has issued to 89, exceeding that of any president since Lyndon B. Johnson, who commuted 226 sentences during his tenure. It also meant that he has commuted more sentences than the last four presidents combined.  In a letter written to each of the inmates in which he personally notifies them that their sentences have been commuted, Mr. Obama says he has chosen them out of the thousands who apply for clemency because “you have demonstrated the potential to turn your life around.”  “I believe in your ability to prove the doubters wrong, and change your life for the better,” Mr. Obama wrote. “So good luck, and godspeed.”  The commutations are part of a second-term push by Mr. Obama to use clemency to correct what he sees as the excesses of the past, when politicians eager to be tough on crime threw away the key even for minor criminals. As a result, African-American and Hispanic men were disproportionately affected.  Mr. Obama had already commuted the sentences of 43 prisoners, as part of an initiative begun last year by James M. Cole, the deputy attorney general at the time. Mr. Cole set criteria for who might qualify: generally nonviolent inmates who have served more than 10 years in prison, who have behaved well while incarcerated and who would not have received as lengthy a sentence under today’s revised sentencing rules.  Mr. Obama plans to spend much of the week talking about a criminal justice overhaul that would include changes to sentencing guidelines, lessening penalties for drug offenders. The president plans to introduce his proposals on Tuesday in Philadelphia before the N.A.A.C.P.’s annual convention.  Overhauling the criminal justice system has become a bipartisan venture. Like Mr. Obama, Republicans running for his job are calling for systemic changes. Lawmakers from both parties are collaborating on legislation. And the United States Sentencing Commission has revised guidelines for drug offenders, so far retroactively reducing sentences for more than 9,500 inmates, nearly three-quarters of them black or Hispanic.  The drive to recalibrate the system has brought together groups from across the political spectrum. The Center for American Progress, a liberal advocacy organization with close ties to the White House and Bill and Hillary Rodham Clinton, has teamed up with Koch Industries, the conglomerate owned by the conservative brothers Charles G. and David H. Koch, who finance Republican candidates, to press for reducing prison populations and overhauling sentencing.  Under the Constitution, the president has the power to grant “pardons for offenses against the United States” or to commute federal sentences. A pardon is an act of presidential forgiveness and wipes away any remaining legal liabilities from a conviction. A commutation reduces a sentence but does not eliminate a conviction or restore civil rights lost as a result of the conviction.  An earlier version of this article referred incorrectly to the number of commutations issued by President Lyndon B. Johnson. It was 226, not 80.
The criminals — all deemed to be nonviolent — were given exceptionally long sentences under old guidelines that the president and many in Congress agree are too stiff.