PORTLAND — A Maine State Police sergeant who pleaded guilty Tuesday to driving drunk will be suspended for 60 days, a penalty that could cost him more than $12,000 in lost wages and benefits.

Robin Parker of Sanford also will be demoted two ranks, from sergeant to trooper, as a result of an internal inquiry by the state police.

Parker was stopped by a trooper on the Maine Turnpike on Dec. 18 after another motorist reported an erratic driver. Parker’s blood-alcohol content of 0.14 percent was just below the threshold of 0.15 percent that requires a minimum of two days in jail, prosecutors say.

Parker appeared before Judge Richard Mulhern on Tuesday morning in Cumberland County Unified Criminal Court. He was read the charge of driving with a blood-alcohol content of at least 0.08 percent, and responded, “I plead guilty.”

Mulhern fined Parker $500 and suspended his license for 90 days as part of a plea agreement with prosecutors, though Parker can get a permit to drive to and from work after 60 days because he has completed the Driver Education and Evaluation Program.

Cumberland County District Attorney Stephanie Anderson said the plea agreement was the same that’s offered to others who plead guilty to a first offense of operating under the influence.

Accompanied by his attorney, Jonathan Goodman, Parker gave a brief statement after leaving the courtroom.

“All I would want to say is I came here today to take responsibility for my actions and I look forward to moving ahead,” he said.

Parker was suspended from the state police for two months without pay, starting Tuesday. He will lose one-sixth of his annual base pay, which in 2011 was $66,000. He also must pay for his own insurance during that period, a cost of about $1,500.

Parker was assigned seven months ago as he permanent state police cadre supervisor at the Maine Criminal Justice Academy in Vassalboro.

Col. Robert Williams, chief of the state police, said he settled on the punishment because of the seriousness of the misconduct, mitigated by Parker’s good record over 17 years with the force.

“Some people would classify this as a victimless crime, but when you look at the potential, what the outcome could have been, the outcome can be very traumatic,” Williams said. “Every day we go out and try to prevent this from happening. We end up cleaning up the result of it. Sometimes those results are deadly.”

Williams said he was impressed by the public apology that Parker emailed to troopers right after the charge became public, taking responsibility for his actions and saying the trooper who charged him did the right thing.

“Here’s a man who put his humility on the line and despite this incident continued to be a role model,” Williams said. “That isn’t something that generally we see in society anymore. Everybody’s got an excuse, whether it’s real or otherwise.”

Sgt. Michael Edes, president of the Maine State Troopers Association, said Parker will not contest the punishment.

“I think Robin got hit extremely hard and fair,” Edes said. “There’s some people that have called for his head, but here’s a case where the state of Maine has thousands of dollars in training invested in this guy. He screwed up bad, but this is a repairable case.”

Goodman said he explored possible defense strategies but opted not to pursue them.

“In the end, we decided this (plea) was what was best in the big picture,” he said. “Typically, defendants in these cases are just really considering the criminal implications. He also had professional implications that had to be considered.”

After his suspension, Parker will be assigned a desk job at the state police barracks in Gray until his driver’s license is fully reinstated. After that, he will be assigned as a trooper in York County, Williams said.

Parker’s case also will be reviewed by the Maine Criminal Justice Academy Board of Trustees, which has the ability to suspend or revoke his law enforcement certificate. It is more common for an officer to sign a consent agreement saying that any new misconduct will lead to automatic suspension.