Outside court, though, Crapo gave an apologetic statement where he acknowledged that he been drinking alcohol on occasion for the past year or so, in violation of the tenets of his Mormon faith.
Crapo said he had been drinking vodka and tonic at his Washington home on the night of Dec. 22, became restless, couldn't sleep and went out for a drive.
He had been driving for about 30 minutes when he realized he was in no condition to drive and started to return home, he said. It was then that he ran a red light and was pulled over in the D.C. suburb of Alexandria, in the early morning hours of Dec. 23.
Crapo registered a blood alcohol level of 0.11 after his arrest, police said, above the legal limit of 0.08. No mention of his blood alcohol level was made at Friday's trial, but a secondary test performed after Crapo was brought to the jailhouse registered at 0.14, according to a law enforcement official with knowledge of the arrest. The official wasn't authorized to release information publicly and spoke on condition of anonymity.
"I am grateful, truly grateful, that no one was injured," Crapo said.
Crapo said he was not with anyone at the time, was not going to see anyone and was not coming or going from seeing anybody.
His arrest stunned colleagues and constituents alike, not only because of his squeaky-clean image but also because he had said he doesn't drink, in accordance with his church's practices.
He said Friday that the night of his arrest was the first time he had ever driven drunk but that he has, in the past year or so, been drinking alcohol on occasion. He apologized for that.
"As a lifelong member of the Church of Jesus Christ of Latter Day Saints, I have endeavored all my life to be an outstanding member" of the church, Crapo said. "I will carry through on appropriate measures for forgiveness and repentance in my church."
Crapo said he felt like he owed people a full explanation of his behavior and took questions outside the courthouse.
In exchange for his plea Friday, prosecutors dropped a charge of failing to obey a traffic signal.
As long as he remains on good behavior, Crapo won't have to serve a 180-day suspended jail sentence.