Story highlights O'Malley's criticism came hours after Clinton told a crowd in New Hampshire that the death penalty has been applied "in a discriminatory way"

O'Malley also criticized Clinton for her Wall Street reform proposals

Washington (CNN) Martin O'Malley said Wednesday that Hillary Clinton is "behind the times" because she supports capital punishment.

The former Maryland governor's criticism of the Democratic presidential front-runner came hours after Clinton told a crowd in New Hampshire that the death penalty has been applied "in a discriminatory way" -- but said she doesn't support abolishing it.

In an interview with CNN's Dana Bash, O'Malley touted Maryland's move to repeal the death penalty -- saying it is "not a deterrent to violent crime" and "can't be administered fairly."

"Secretary Clinton is often a bit behind the times in terms of actually what works when it comes to policy," O'Malley said. "I respect her. I have a great deal of respect for her, but she's often late to many of these issues because she's of a different generation than I am."

Clinton has long backed the death penalty -- saying in her 2000 run for Senate that it had her "unenthusiastic support" and maintaining that position in her 2008 run for president.

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