America’s top law enforcer is calling for changes to the country's criminal justice system including scaling back minimum sentences for minor drug offences, aimed at easing overcrowded prisons.

In a speech at the American Bar Association in San Francisco, Attorney General Eric Holder said he is mandating a change to Justice Department policy so that low-level, non-violent drug offenders with no ties to drug gangs will not be charged with offences that impose mandatory minimum sentences.

Many defendants convicted of low-level offences would be diverted to drug treatment and community service programs and expand a prison program to allow for release of some elderly, non-violent offenders.

The United States has the world’s highest incarceration rate, both per capita and by the total number of inmates, more than 2.2 million prisoners.  China’s jails hold about half the number of prisoners as America, despite having more than three times the population.