Sen. Mike Crapo (R-Idaho) pleaded guilty on Friday to driving under the influence.
The senator from Idaho is also required to participate in an alcohol safety program. Crapo will reportedly not have to serve a 180-day jail sentence if his behavior is good.
In late December, Crapo, a Mormon, was arrested in Northern Virginia for running a red light. At first, police registered a blood alcohol level of 0.11 percent. Another, later test found Crapo's blood alcohol level at 0.14 percent.
Crapo's decision to plead guilty follows a statement from his office saying he did not plan to contest the charge. Crapo's office also released a statement in which he said he was "deeply sorry."
"I made a mistake for which I apologize to my family, my Idaho constituents and any others who have put their trust in me," Crapo said in the statement. "I accept total responsibility and will deal with whatever penalty comes my way in this matter."
The Senate Ethics Committee, which is authorized to investigate "violations of law," declined to say whether it will look into the matter.
This article was updated at 10:55 a.m.