The 15-year-old is believed to have supplied the other suspects with the gun used in the shooting.
A little before 2 p.m. on Sunday, Visalia Police found a man with a gunshot wound. Terry Wade III, 19, later died at Kaweah Delta Medical Center.
Police believe the shooting was the result of a drug deal robbery.
RELATED: 19-year-old shot dead after suspected drug deal goes wrong in Visalia
The three 18-year-olds accused of killing him are Noah Fox, Jose Cortez, and Kalvin Solis. They were arraigned together at the Tulare County pre-trial facility today.
Wade's family was also there.
"He was a caring person, he really was," said Janice Fielder, Wade's aunt. "People don't know that, but I'd like (everyone) to know he was really a very loving person."
The suspects' next court date is set for June 12th
A 17-year-old was also arrested in connection with the case.
Wade's family has set up a GoFundMe account. They've also set up an account with Wells Fargo.
The customer name is Jami D Jump.
The account number is 1147690521.