Will we cost out Capital Punishment soon?

Mr. O’Malley, a Democrat and a Roman Catholic who has cited religious opposition to the death penalty in the past, is now arguing that capital cases cost three times as much as homicide cases where the death penalty is not sought. “And we can’t afford that,” he said, “when there are better and cheaper ways to reduce crime.”

Lawmakers in Colorado, Kansas, Nebraska and New Hampshire have made the same argument in recent months as they push bills seeking to repeal the death penalty, and experts say such bills have a good chance of passing in Maryland, Montana and New Mexico.

Death penalty opponents say they still face an uphill battle, but they are pleased to have allies raising the economic argument.

Efforts to repeal the death penalty are part of a broader trend in which states are trying to cut the costs of being tough on crime. Virginia and at least four other states, for example, are considering releasing nonviolent offenders early to reduce costs.