"Acknowledging that you're not a perfect person is one of the hardest things in the world to do," said McKown, whose last day will be Aug. 13. "I have faults. And I make mistakes."

As first reported at heraldonline.com Tuesday afternoon, a governor's office spokesman said McKown's letter of resignation is expected to arrive in Columbia this week.

The announcement comes on the heels of an incident in Lincoln County, N.C., Thursday night where authorities say McKown was drinking beer while driving a county vehicle and traveling with a man suspected of smoking crack cocaine.

McKown, 39, was arrested the following day in York County on a charge that he violated his probation by lying to a probation agent about his North Carolina arrest, not immediately notifying an agent of his arrest and leaving the state without permission, among other offenses.

McKown was sentenced to a year's probation after being convicted in May of unlawfully possessing a prescription drug, a misdemeanor charge tied to a half-pill of Viagra that police found in his home.

Despite the misdemeanor conviction, McKown was acquitted of felony cocaine charges, the same allegations that led Gov. Mark Sanford to suspend him from office in 2006.

Because he was acquitted of the more serious charges, McKown was able to return to the coroner's office last month. But he said Tuesday that he'd struggled adjusting to the job.

"It was kind of like getting up and just going through the motions," he said. "Had I not went back, I wouldn't have known that, perhaps, my heart just wasn't in it."

During his time back in office, he responded to only one death call.

Now, McKown says he's focused on a hearing next week that will determine if his probation case moves forward. If a circuit court judge hears his case, he or she could force McKown to serve a year in prison.

"I need to concentrate on getting my life back together," McKown said. "I need to concentrate on following the orders of my sentencing and getting past this."

McKown maintains he wasn't drinking when police stopped him in North Carolina last week. He claims he didn't know his friend, 43-year-old Eric Howell of Gastonia, N.C., was drinking in the vehicle until police pulled them over.

He admitted there was beer in the SUV, and said that is reason enough for him to step down.

"The bottom line is, I probably should have never been in that car to start with," McKown said. "I acknowledge that I made a mistake. And I acknowledge that it was a mistake that would probably make the public think I have betrayed their trust. So that within itself warrants my resignation."

McKown's announcement comes a day after the York County Council stripped him of the county-owned Chevrolet Blazer he's been driving.

"We wanted to make the public aware that we're concerned about his actions," County Council Chairman Buddy Motz said after Monday night's meeting. "We, in a small way, needed to deal with it."

McKown said he plans to turn the vehicle over to the county today. He said the county doesn't have a policy about when and where employees drive cars. He contends that other elected officials drive county vehicles to churches and restaurants.

McKown also says he should be able to drive a county vehicle anytime because he's always on call.

He wasn't scheduled to respond to calls Thursday night.

Despite McKown's claims, county vehicles are supposed to be used for county business, said Cathy Hazelwood, general counsel for the state Ethics Commission.

Although she couldn't say if McKown violated state ethics laws, she said McKown's trip to North Carolina sounds "problematic."

"If you leave the area, how can you be on call?" she asked.

In a 1997 letter to the Ethics Commission, McKown asked if he could use his county vehicle on personal trips because he is always on call.

The answer was no.

McKown expects chief deputy coroner David Chambers will run the office after he leaves next month. McKown was appointed to the coroner's post in December 1994 and was the youngest coroner in the state at the time of his appointment. A Republican, he was elected to a full term in 1996. He was re-elected in 2000 and 2004. A new coroner will be elected in November.

While in office, McKown's main job was to investigate all unexplained or unattended deaths, including homicides, suicides and accidents. He also signed death certificates and determined causes of death.

McKown said he hopes his legal troubles won't diminish what he's done in his career.

"I don't want two or three blemishes on my record to be my legacy," he said. "I think a life full of helping people and doing things for people isn't going to be ruined by an error in judgment."