US President Barack Obama has commuted the prison sentences of 46 drug offenders as part of a renewed effort to reform the criminal justice system.US President Barack Obama

In a video announcement, he said the prisoners were not “hardened criminals” and had been given sentences that “didn’t fit their crimes”.

He said it was part of a wider effort to restore the sense of fairness in a “nation of second chances”.

Mr Obama is due to unveil plans for criminal justice reforms on Tuesday.

The 46 prisoners, 14 of whom were serving life sentences, are scheduled to be released on 10 November.

Most of them were jailed for crack cocaine offences, which once carried a sentence equivalent to someone caught with 100 times the same amount of powder cocaine.

“These men and women were not hardened criminals. But the overwhelming majority had to be sentenced to at least 20 years,” Mr Obama said.

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

‘Prove doubters wrong’

In a letter to one of the prisoners, Mr Obama said he was granting the applications because “you have demonstrated the potential to turn your life around”.

The letter ended: “I believe in your ability to prove the doubters wrong, and change your life for the better. So good luck, and Godspeed.”

Mr Obama has now commuted the sentences of 89 prisoners, with most being non-violent drug offenders who applied for clemency under an initiative that began in April 2014.

A commutation leaves the conviction in place, but ends the punishment.

Some of those to be freed

• Larry Darnell Belcher (Martinsville, Virginia) – Found guilty of intent to distribute cocaine and possession with intent to distribute marijuana. Sentenced to life imprisonment in 1997.
• John L Houston Brower (Carthage, North Carolina) – Found guilty of distributing crack cocaine. Sentenced to life imprisonment in 2002.
• Anthony Leon Carroll (Tampa, Florida) – Found guilty of possession with intent to distribute crack cocaine. Sentenced to 21 years in prison in 1999.
• Steven D Donovan (Oak Creek, Wisconsin)- Found guilty of conspiracy to possess with intent to distribute cocaine; interstate travel to promote distribution of cocaine; possession with intent to distribute cocaine. Sentenced to life imprisonment in 1992.

In a statement, White House counsel Neil Eggleston said Mr Obama is likely to issue more commutations before leaving office in 2017.

But he added that “clemency alone will not fix decades of overly punitive sentencing policies”.

President Obama is due to lay out his plans for criminal justice reform in a speech to the National Association for the Advancement of Colored People (NAACP) in Philadelphia on Tuesday.

On Thursday, he is expected to become the first sitting president to visit a federal prison when he goes to the El Reno Federal Correctional Institution outside of Oklahoma City.

This week’s focus on criminal justice signals a renewed bid by Mr Obama’s administration to tackle what he sees as a lack of fairness in the system.

The last significant changes came in 2013 when US Attorney General Eric Holder dropped mandatory minimum sentences for non-violent drug offenders.

Federal prisons in numbers

• Some 208,000 people are behind bars in federal prisons in the US
• Nearly 50% of them are there for drug offences
• About 37% of prisoners are black, while 34% are Hispanic
• The cost of incarceration in the US was $80bn (£50bn) in 2010

Source: Department of Justice, Federal Bureau of Prisons