The Justice Department is broadening the criteria it will use in evaluating clemency petitions from certain federal prisoners and expects the changes to result in thousands of new applications, Attorney General Eric Holder said Monday. 

The new criteria, which will be detailed later this week and are aimed at inmates serving time for nonviolent drug offenses, are intended to both reduce the nation's federal prison population and also "ensure that those who have paid their debts have a chance to become productive citizens," Holder said in a video message. 

The announcement is part of an ongoing Obama administration push to re-evaluate sentences for drug crimes that officials believe were unduly harsh and were imposed under old federal guidelines that treated convictions for crack cocaine offenses more harshly than those involving the powder form of the drug. 

In December, President Obama commuted the sentences of eight drug prisoners, and the Justice Department in January publicly encouraged defense lawyers from around the country to help some drug prisoners prepare petitions for clemency. 

The Justice Department says it expects thousands of new applications because of the expanded criteria. Dozens of additional lawyers will be assigned to handle those applications.