BOSTON (AP) — As Massachusetts governor, Republican Mitt Romney set himself a daunting challenge: craft a death penalty law that virtually guaranteed only the guilty could be executed, then push it through an overwhelmingly Democratic state Legislature that was leery of capital punishment.

Making the task even more difficult, the push by Romney — who is now running for president — came in 2005 at a time of growing national skepticism about the death penalty. Just two years earlier, Illinois Gov. George Ryan had cleared his state’s death row after the death sentences of several inmates had been overturned.

Romney decided to tackle that skepticism by coming up with what he said would be a “gold standard for the death penalty in the modern scientific age.”