MOSES LAKE - Grant County Sheriff's Deputy John McMillan rolled his patrol car while responding to a disturbance in Mae Valley, near Moses Lake, Wednesday night.

The 40-year-old deputy was treated for minor injuries at Samaritan Hospital and released after three hours, according to Sheriff Tom Jones. The deputy was allowed to rest at his Ephrata home.

McMillan was traveling southbound on state Route 17 when he reportedly lost control of the car while trying to turn onto Grape Drive, according to the Washington State Patrol.

"Deputy McMillan's vehicle slid on standing water in the roadway, causing him to lose control of the car. The standing water was caused by heavy rain," stated Kyle Foreman, Grant County Sheriff's Office public information officer.

The 2010 Ford Crown Victoria patrol car left the road, rolled, struck a power pole and ended on its top.

McMillan was responding to a disturbance on Fifth Street Northeast in May Valley, near Moses Lake, at 11:23 p.m.  with his emergency lights activated, according to the state patrol.

The disturbance involved three men and an assault with a pipe, according to the sheriff's office. A male victim told deputies the suspect approached his home, trying to pick a fight, and struck him on the hand with a pipe. The suspect agreed he hit the victim, but said it was in self-defense because he feared retaliation by the victim and another man from a previous encounter.

McMillan has been a deputy for two years and hasn't had any previous accidents while on duty.

"He's a great guy. He worked for me in the drug task force and went over to the patrol side," said Jones.

The state patrol is investigating the cause of the wreck, which destroyed the car.

After the cause is determined, the sheriff's office will convene a driving review board to determine if the wreck was preventable.

"If it is deemed preventable, we would move on with disciplinary actions," said Jones.

There are few serious accidents involving sheriff's office patrol cars and Jones noted they have a good driving record considering then number of deputies and the amount of time spent driving.

"They drive a couple hundred of miles a day," said Jones.