CONNECTICUT IS set to become what Maryland should have been: the most recent state to abolish capital punishment.

With the expected signature of Gov. Dan Malloy (D) within the next few days, Connecticut would become the 17th state to repeal the death penalty and the fifth in the past five years. Life without the possibility for parole would become the highest level of punishment in the state, which last executed a prisoner in 2005.

Connecticut’s action is disconcerting in one important respect: The repeal takes the death penalty off the table for future cases but keeps in place the sentences for the 11 prisoners already on death row. This decision was taken in part to preserve the death sentences of two career criminals who, during a 2007 home invasion, raped and murdered a mother and her two daughters and then set their home on fire to destroy evidence.

We share in the outrage triggered by such heinous crimes, but we also believe that the death penalty — no matter the facts of a case — is morally wrong. One does not have to subscribe to this view to believe that it is also indefensible as a matter of policy.

Once an execution has been carried out, there is no chance for reversal. And there is no level of certainty that can guarantee a grievous mistake will be averted. Roughly 140 death-row inmates have been exonerated since 1973, many after serving years on death row or coming close to execution.

There is also no evidence that capital punishment deters the most violent crimes. But a capital case often sucks millions of dollars from public coffers because defendants must be provided with more than one lawyer and other resources. Even after a conviction, these cases drag on for years, taking a toll on victims’ families.

All of these factors are well known to Maryland lawmakers, who just three years ago came within one vote of repealing the death penalty. Add to that historical racial disparities in how the penalty has been applied and the reluctance of the state to carry out such sentences. Only five menare on Maryland’s death row, and no prisoner has been executed since 2005.

Yet Maryland’s lawmakers refused to seriously consider repeal during the recent legislative session. Connecticut’s approach may be imperfect, but lawmakers there at least had the fortitude to act.