Vigil is scheduled to be sentenced April 15.
Aggravated murder carries a sentence of 25 years to life in the Utah State Prison, while the punishment for the other count is five years to life in prison. According to the plea agreement, prosecutors are recommending that Vigil be sentenced to life with the possibility of parole, and will ask for the sentences to run concurrent.
Vigil was arrested after he opened fire outside his parents' home on July 28, unloading at least 10 shots across a city block.
When police arrived, Antonio David Vasquez, 33, was found dead in the yard with a gunshot wound to the head. Lee Norton Otero, who had been visiting the family at home near 450 N. Grant St. (760 West), was shot in the chest and arm.
Police said Vigil chased Otero down the block, shooting.
The bloody aftermath left an 8-year-old boy in a nearby car grazed by a bullet, several 9mm shell casings in the yard and bullet holes in cars and buildings from 400 to 500 North, according to court documents.
Authorities have never revealed a motive for the shootings.
Vasquez's sister, 26-year-old Danielle Lucero, was one of three people who were shot and killed in a Midvale home on Feb. 12.