The incident started near Plainview around 8 pm.
Police say 31-year-old Roberto Govea led the other driver to his home on Ellis Place in Porterville.
That's when Govea's girlfriend, 34-year-old Lyndsey Smothers, came out of the house and allegedly handed him a loaded pistol.
Police say Govea pointed the gun at the other driver from his driveway and then fired a shot into the air as the person drove away.
After getting a search warrant, Porterville police found the gun inside the house. They also discovered some methamphetamine.
Officers arrested Govea on several charges, including assault with a deadly weapon, conspiracy to commit a crime, discharge of a firearm with gross negligence and possession of meth.
Smothers was also arrested for conspiracy and possession of meth.