Story highlights Both houses of Maryland's legislature have now voted to ban the death penalty

Gov. Martin O'Malley has pledged to sign the bill

O'Malley says ending the death penalty is a "moral responsibility"

Maryland will be the sixth state in six years to end capital punishment

By a margin of 82-56, the Maryland House of Delegates voted Friday to ban the death penalty in that state. The bill now goes to the desk of Gov. Martin O'Malley, who has pledged to sign it.

"To govern is to choose, and at a time where we understand the things that actually work to reduce violent crime, when we understand how lives can be saved, we have a moral responsibility to do more of the things that work to save lives," O'Malley said at a news conference.

"We also have a moral responsibility to stop doing the things that are wasteful, and that are expensive, and do not work, and do not save lives, and that I would argue run contrary to the deeper principles that unite us as Marylanders, as Americans, and as human beings," O'Malley added.

NAACP President Benjamin Jealous called the action "what courageous, principled political leadership looks like," and Archbishop of Baltimore William Lori said he applauded the general assembly "for choosing to meet evil not with evil, but with a justice worthy of our best nature." O'Malley thanked both the NAACP leadership and the state's faith leaders for their support.

Baltimore County state attorney Scott Shellenberger, a prominent opponent of the bill, said eliminating capital punishment was unnecessary, since Maryland's current policy is judicious and one of the "most restrictive in the country."

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Since a law was passed in 2009, a judge can impose death in Maryland only if one of three factors exists: DNA evidence, a videotaped confession or a videotaped murder.

Maryland has executed only five people since 1976, one of whom Shellenberger prosecuted in the '80s.

Delegate Neil Parrott, a Washington County Republican, said most state residents don't want to see the death penalty abolished, but the governor and the "Annapolis eite" used political arm-twisting to push the bill through the legislature.

But Parrott said the death penalty move "does open a door" to petition, or challenge, such a law and bring it up for a referendum. Parrott has set up mdpetitions.com, a website devoted to pursuing petitions targeting laws "passed by a liberal-leaning legislature in Annapolis that simply do not make sense."

Parrott says it's too early to say how opponents of the ban will proceed if and when the bill is signed. He said it's "excruciatingly difficult" to get a petition on the ballot, but members of mdpetitions.com will be consulted on what to do.

O'Malley will make a case-by-case decision regarding the state's five current death row inmates, according to a statement from the governor's office.

Lt. Gov. Anthony Brown called Friday "a great day for Maryland."

"We saw a death penalty, a long history of racial bias, inaccuracies, injustices, and today, we decided that as a state we could do better. Today is a victory for those who believe that fairness and truth and justice, and not retribution or bias, are fundamental to our core beliefs as Marylanders," Brown said.

Shellenberger said confining the racial argument to the state of Maryland, four studies on the issue have ascertained "no purposeful racial discrimination done on anyone in any of those cases."

And when it comes to the retribution argument, Shellenberger said he believes in "the deterrence of one," when a person is convicted of a heinous murder beyond a shadow of doubt, "Every person will never be subjected to that person killing again."

O'Malley introduced the legislation in January.

The state Senate approved the bill last week.

Maryland will become the sixth state in as many years to replace capital punishment with life in prison without parole. Currently, 33 states, plus the federal government and the U.S. military, have the legal option of imposing the death penalty, while 17 plus the District of Columbia do not.