Maryland will become the 18th state to abolish capital punishment, but futures of five convicted murderers up in the air

Five death row prisoners in the state of Maryland are now in a state of legal limbo after the state's House of Delegates voted on Friday to repeal the death penalty, making its abolition now certain.

Maryland will become the 18th state to abolish capital punishment in the US when its governor Martin O'Malley signs the ban into law. That is now a foregone conclusion, following the House vote by 82 votes to 56 on Friday, as O'Malley has been a leading campaigner for repeal.

But the reform will lead the state's existing five capital inmates stuck where, in the case of three of them, they have been since 1983 – on death row. The repeal will not be retroactive, and any move to commute their sentences to life without parole can only be made by O'Malley himself or by the courts.

The five men – John Booth-El, Vernon Lee Evans, Anthony Grandison (all put on death row in 1983), Heath Burch (1995) and Jody Miles (1997) – will not be able to draw much succor from the example of governors in other abolition states, as their approaches have differed. In the case Illinois, which repealed the practice in 2011, every prisoner on death row had their death sentences commuted to life by the governor.

On the other hand, Connecticut and New Mexico decided to leave their death row inmates where they were.

With repeal now inevitable, all eyes will turn to O'Malley for any clues as to his thinking about what to do with the five. In Maryland, the governor has sole power outside the judiciary to grant clemency or commute sentences.

At face value he could opt to go either way. As a Democratic politician, he might be expected to lean towards commutation, but in his time as governor he's granted only 50 pardons out of almost 700 petitions put before him and he's also a likely candidate for the Democratic presidential nomination in 2016 which might encourage him to strike a tough-on-crime pose.

But Richard Dieter of the Death Penalty Information Center, one of the country's foremost experts on capital punishment, said he expected O'Malley to close death row entirely. "I would be surprised if he left the five men there – to leave people on death row while no future sentences are given would be quite extreme."

Maryland has been one of the least active death-penalty states in the US, with its last execution taking place in 2005 and no new death sentences meted out since O'Malley entered the governor's mansion in 2007. But as a gateway state to the South, it carries a symbolic significance: the overwhelming majority of executions are now carried out in the southern states.

Maryland will also become the sixth state in six years to effect repeal, suggesting that a wind of change is blowing through America. The previous five states were Connecticut, Illinois, New Jersey, New Mexico and New York.

Jane Henderson, director of the repeal campaign Maryland Citizens Against State Executions said that she also expected O'Malley to commute the sentences of the five. She said the prisoners had committed "five horrible murders, although there's no rhyme or reason why these particular five are on death row while other horrible crimes didn't end up there – that's the lottery that is the death penalty."