(CNN) -- Gov. Bill Richardson of New Mexico will not pardon legendary Wild West outlaw Billy the Kid in the death of a law enforcement officer more than a century ago, he said Friday.
Richardson made the announcement on ABC's "Good Morning America" the same day he leaves office.
The issue facing Richardson was whether one of his predecessors, Gov. Lew Wallace, promised about 130 years ago to pardon Billy the Kid -- known more formally as William H. Bonney -- for killing Sheriff William Brady of Lincoln County, New Mexico.
Wallace has long been said to have promised a pardon if Bonney testified before a grand jury that was investigating another killing. Wallace did not follow through on that promise, many say, and the reasons are debated.
Richardson said he believes that Wallace did promise to pardon Bonney. Yet there is "historical ambiguity" about why Wallace did not follow through, Richardson said, and he did not want to second-guess the former governor's decision.
"It was a very close call," Richardson said. "The romanticism appealed to me to issue a pardon, but the facts and the evidence did not support it."