Richard Jefferson Saterfield, 21, turned himself in to homicide detectives Saturday.
On Friday, authorities arrested the first suspect, 20-year-old Hieu Hoang.
Both Saterfield and Hoang have been charged with the murder of brothers 19-year-old Daniel Robert Murti and 15-year-old Sergio Murti.
On Thursday, May 11, just after 12 p.m., officers responded to the shooting in a parking lot near 5200 Fruitridge Road and Stockton Boulevard.
Witnesses heard several gunshots in the area and observed at least two suspects in a light-colored SUV flee the scene east of Fruitridge Road.
When deputies arrived on scene, they found two male victims on the ground in the parking lot of a strip mall. They were both pronounced dead at the scene.
Family says the two were walking to the store when they were gunned down.
Homicide detectives are still investigating the motive behind the shooting but believe the victims and suspects had a prior encounter.
Saterfield has been charged with two counts of murder and is being held in the Sacramento Main County Jail.