The decision gives lawyers for Steve David Garcia an opportunity to prove that he was involuntarily intoxicated when he hit his wife with a hammer and drove over her, the Denver Post reports. If they succeed, Garcia could get a new trial.
The ruling was the first of its kind in Colorado although courts in Washington and Texas have made similar ones.
Garcia attacked his wife in 1999, three days after she told him she wanted a divorce. His lawyers say that he had given himself a large dose of insulin because he expected to be eating ice cream and cake at his daughter's birthday party but had not eaten anything when he hit his wife.
The lawyers claim that he was in a hypoglycemic state that had much the same effect as drinking.