A Des Moines man found shot to death in October 2021 was murdered by the man he was meeting to purchase drugs, a Polk County jury found Friday.

Kalvyn Kline, 21, was killed early Oct. 22, 2021. Police responding to reports of gunshots outside a Hull Avenue apartment building found him slumped behind the wheel of a car with numerous wounds, and he was declared dead at the scene. He left behind a wife and two children.

Police charged Darren Diggs, 29, with first-degree murder in Kline’s death. Diggs, a resident in the nearby building, was known to sell controlled substances, according to investigators, and Kline before his death was addicted to the anti-anxiety medication Xanax. Phone records showed he made several calls to Diggs’ phone shortly before the 5:30 a.m. shooting.

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Unusual ammunition + math makes a match

During Diggs’ trial, which began Monday, prosecutors drew additional connections between Diggs and the shooting. Video footage from the apartment building showed a man leaving and reentering the building about the time of the shooting, wearing a distinctive sweatshirt matching one found in Diggs’ apartment.

Police also found a pistol in the apartment that ballistics experts matched to spent shell casings found at the scene, and a half-empty box of the same uncommon brand of ammunition. Between the box, several magazines of ammunition and the shots fired at the scene, investigators were able to account for all 50 rounds that came in the box.

Diggs had one of those magazines, as well as Xanax pills, on his person when he was arrested. During the ensuring interrogation, police said he gave inconsistent answers about whether and why he’d left the building that morning and whether he’d had his gun at the time. At one point, officers asked if they could swab Diggs’ hands for gunshot residue, then left him alone in the interview room with a bottle of water. Video footage appeared to show Diggs attempting to surreptitiously wash his hands with the water after they left.

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Defense argues state couldn’t prove defendant was shooter

Investigators never determined a motive for the shooting, but prosecutor Jaki Livingston told jurors Thursday they had all they needed to find Diggs guilty.

“Nobody knows what happened in that car,” she during closing arguments. “… We don’t know what made Mr. D decide to use that gun. But we know that he did, and he did so more than once.”

Diggs did not testify or offer any witnesses in his defense. His attorneys argued that prosecutors couldn’t prove Diggs was the shooter.

“Identity is an element the state has to prove beyond a reasonable doubt, and the state has failed to do that,” defense attorney Wendy Samuelson said in her closing argument.

Sentencing date to come, but life is mandatory

The jury received the case at noon Thursday and returned their verdict of guilty just after noon Friday.

Diggs will be sentenced at a later date. Under Iowa law, the mandatory sentence for first-degree murder is life in prison without parole.

William Morris covers courts for the Des Moines Register. He can be contacted at wrmorris2@registermedia.com or 715-573-8166.

This article originally appeared on Des Moines Register: Darren Diggs of Des Moines convicted in 2021 murder of Kalvyn Kline