Recently, President Obama began to use his constitutional pardon power in a more systemic way. His focus, after 46 grants of commutation in July, is now clear: He wants to reduce the length of some extraordinarily long prison sentences imposed on nonviolent drug offenders during the height of the so-called "War on Drugs."

Surprised by the exercise of a constitutional power that had atrophied in recent years, critics are now expressing concern about Obama's use of this power to address overincarceration for a certain type of crime. (In the Wall Street Journal, Paul H. Robinson opined that clemency should be "focused on the unique facts of the case at hand," rather than used to correct broad categories of injustice. In addition, several members of Congress wrote to the attorney general to suggest that the president was improperly using clemency "to benefit specific classes of offenders.") But these critics deeply misunderstand the foundation of the pardon power as well as its historical tradition.

In Federalist 74, Alexander Hamilton explained why the framers of our Constitution believed "humanity and good policy [meant] the benign prerogative of pardoning should be as little as possible fettered or embarrassed." Echoing the sentiments of many framers, Hamilton explained the benefits of permitting the president to use the pardon power to benefit classes of offenders, if and when needed, to heal the nation from rebellion, dissent, or during those times when the severity of the criminal code wears "a countenance too sanguinary and cruel."

The founding fathers' actions as presidents, too, showed that they believed clemency was a tool that could and should be used broadly for classes of offenders. George Washington first used the pardon power to free the leaders of the Whiskey Rebellion. Thomas Jefferson pardoned all of those convicted under the Alien and Sedition Act because he believed the law was unconstitutional. In judging the proper and intended use of the tools provided for in the Constitution, we should be guided by the words and deeds of Hamilton, Washington and Jefferson, rather than by the criticisms of pundits and politicians.

Notably, until the modern "tough-on-crime" political era, presidents made extensive use of the clemency power — and often did so on behalf of "specific classes of offenders." Abraham Lincoln pardoned Army deserters, Andrew Johnson pardoned Confederates and Woodrow Wilson expressed his disagreement with the Volstead Act by granting clemency to hundreds of people convicted of alcohol-related offenses. After each war since the Civil War, presidents have used clemency powers to benefit draft evaders and army deserters. Most recently, Gerald Ford granted more than 14,000 such clemencies in just one year in the wake of the Vietnam War.

Obama's use of clemency to address excessive sentences from the war on drugs isn't contrary to principle and history — it carries a rich heritage forward.

Importantly, though the president's staff highlights that he has now commuted more federal sentences than any president since Lyndon Johnson, the scope and nature of his clemencies must be evaluated in light of the massive modern growth in the number of federal prisoners and the severity of their sentences. When Johnson in 1965 commuted 80 federal prison sentences, there were only about 20,000 federal prisoners, and most had a chance to earn release on parole. Move ahead 50 years — parole opportunities have been entirely abolished in the federal system, and the federal prison population now exceeds 200,000. Obama's grant of clemency to a few dozen of the nearly 100,000 (mostly African-American and Latino) federal prisoners serving long, fixed prison terms for drug offenses is a far cry, factual speaking, from benefiting an "entire class of offenders" as some critics have charged.

In an article for the Heritage Foundation decrying the clemency failings of recent presidents, legal scholar Paul Rosenzweig stressed that "the pardon power, properly understood, is one of the great bulwarks of individual liberty [because it is] the personification of the government acting as a check on the institutions of the government." Obama's effort to reinvigorate the pardon power marks a return to — not a departure from — the proper use of a balancing tool that the Constitution created as a balm to internal divisions and as a means to heal wounds to our nation's commitment to individual liberty created by other institutions.

For those who frequently complain that Obama too often fails to respect our Constitution and personal liberty, his recent commutations should be an occasion to celebrate, not criticize, a small group of Americans now experiencing a new birth of freedom.

Doug Berman is a criminal-law professor at the Ohio State University and is author of the blog Sentencing Law and Policy. Mark Osler is a criminal-law professor at the University of St. Thomas and teaches the nation's first federal commutations-law clinic.