Just before 2 a.m. on March 8, the victim reportedly began arguing with a man at Harry's Sportsman Lounge at 833 Texas St., Fairfield police said.
The two left the bar and continued their argument outside, where the suspect allegedly went to the cab of his truck and retrieved a handgun.
The suspect, identified as 51-year-old John Davis of Fallon, Nev., then shot the victim in the upper left leg and drove away before police arrived. The victim's injuries were not life-threatening, police said.
Officers have not been able to find Davis, who is described as a white man with a thin build and long, straight hair. He has a multi-colored, goatee-style beard, police said.
The suspect's vehicle was described as a late 90s model Ford F-150 truck with an extended cab. It had a tan-colored camper shell and possibly Nevada license plates.
A warrant was issued for Davis' arrest out of Solano County for assault with a deadly weapon.
Anyone with information about the incident is asked to call Fairfield police at (707) 428-7300 or Solano County Crime Stoppers at (707) 644-STOP.