A key state’s witness against the Arizona rancher accused of killing a Mexican citizen in January had previously served prison time for smuggling cannabis across the Arizona-Mexican border in 2015.

Court documents reveal the witness carried a nearly 50-pound cannabis bundle in a backpack into the U.S. near Sonoita, AZ. The man, whose name is not revealed by the state, accepted a plea agreement to misdemeanor possession of cannabis and served nearly seven months in prison.

The witness claims he saw the Jan. 30 shooting of Gabriel Cuen Buitimea, 48, and identified George Alan Kelly as the shooter.

Kelly, 75, has been charged with second degree murder and two counts of aggravated assault in the shooting and killing of Buitimea.

The witness was only identified by his initials, D.R.R., during a preliminary evidentiary hearing in February where he reenacted Buitimea’s death during a dramatic testimony, according to AZCentral.com. The witness claims to have been traveling with Buitimea alongside a group of men crossing Kelly’s property when they reportedly began taking fire. The witness appeared for his testimony in a blue medical face mask, a black sweatshirt and a blue hoodie pulled over his head to conceal his identity.

The state interviewed the witness before February’s hearing when he said he had never transported drugs into the U.S., according to a motion filed Kelly’s defense attorney, Brenna Larkin.

Larkin has argued that Kelly shot in self-defense over the heads of a group of armed men walking through his property. Kimberly Hunley, chief deputy Santa Cruz County attorney, has alleged that Kelly shot Buitimea in the back as he was fleeing for his life, ultimately killing him.

According to Larkin, Kelly heard a single gunshot Jan. 30 as he was having lunch with his wife. Kelly saw his horse get spooked and run away before noticing a group of men, armed with AK-47 rifles, moving through the trees near his home.

Kelly is currently free on a $1 million surety bond and is scheduled to appear for two more hearings in August before his trial is set to begin on September 6.

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