The officer who fatally shot Philando Castile during a traffic stop last year told investigators that the smell of "burnt marijuana" in Castile's car made him believe his life was in danger.

"I thought, I was gonna die," Officer Jeronimo Yanez told investigators from the Minnesota Bureau of Criminal Apprehension fifteen hours after the shooting. "And I thought if he’s, if he has the, the guts and the audacity to smoke marijuana in front of the five year old girl and risk her lungs and risk her life by giving her secondhand smoke and the front seat passenger doing the same thing then what, what care does he give about me. And, I let off the rounds and then after the rounds were off, the little girls was screaming."

This isn't the first time a police officer has cited the alleged danger posed by pot to justify a confrontation that turned deadly. Last year North Carolina police officers decided to confront Keith Lamont Scott in his car after observing him smoking marijuana in it.

Like Castile, Scott was a black man. And like Castile, police were aware that Scott had a firearm. "Due to the combination of illegal drugs and the gun Mr. Scott had in his possession, officers decided to take enforcement action for public safety concerns," the police department said in an incident summary.

But officers' claims of safety concerns about marijuana are difficult to reconcile with what researchers know about the effects of marijuana use. Numerous studies have demonstrated that marijuana tends to decrease aggression in people under its effects. Both drug policy experts and the general public rate marijuana use as less harmful to individuals and society than the use of most other drugs, particularly alcohol.

Yanez's statement is somewhat puzzling, conflating secondhand smoke exposure with a clear and present danger to an officer's life.

Regardless, Yanez's defense sought to make Castile's marijuana use a central issue in Yanez's manslaughter trial. Castile had THC (the main psychoactive compound in marijuana) in his system at the time of the stop. But because of the way the chemical is absorbed by the body, blood THC levels are a poor indicator of current intoxication. It's unclear whether Castile was actually impaired at the time.

Yanez's attorneys nevertheless attempted to convince a judge that the manslaughter case should be thrown out because Castile was "stoned" and hence partially culpable in his own death.

"The status of being stoned (in an acute and chronic sense) explains why Mr. Castille: 1) did not follow the repeated directions of Officer Yanez; 2) stared straight ahead and avoided eye-contact; 3) never mentioned that he had a carry permit, but instead said he had a gun; and (4) he did not show his hands," the lawyers wrote in a motion to dismiss the charges against Yanez.

That motion failed, but Yanez's lawyers pressed the issue throughout the trial. According to a recap of the case's closing arguments in the Pioneer Press, "Had it not been for Castile’s decision to 'get stoned' on marijuana before operating a vehicle while armed with a gun, and further his decision to 'ignore' Yanez’s commands not to reach for his firearm, 'none of this would have happened, [defense attorney Earl] Gray told jurors."

Yanez was ultimately acquitted.