WARNING: The video below is uncensored and may be disturbing to some viewers.
The shooting on July 6 a year ago, in the Minneapolis suburb of Falcon Heights, gained widespread attention because Mr Castile's girlfriend, Diamond Reynolds, live-streamed its gruesome aftermath on Facebook.
Police dashcam footage of Castile's death that was shown during Yanez's manslaughter trial was released to the public Tuesday, the Washington Post reports. According to Yanez's testimony, he feared that Castile-who had informed him upon being pulled over that he was in possession of a firearm-was reaching for his gun, so shot him dead in self-defense.
The statement appeared in the transcript of Yanez's questioning by investigators last July, in which Yanez also failed to reveal that Castile had said he was "not reaching" for his handgun.
In the video, you can see Yanez coming up to the vehicle and saying, "Your break lights are out", informing Castile that one break light is out, as Diamond Reynolds claimed. "Sir, I have to tell you, I do have a firearm on me", Castile said.
Less than 30 seconds after Yanez fired the shots, the dashcam video shows a young girl - Reynolds' daughter - slowly get out of the back seat of the auto before being grabbed by another officer.
The squad-car video shows Yanez approaching Castile's auto and asking for a driver's license and proof of insurance.
Millions have already seen the footage thanks to Castile's girlfriend, Diamond Reynolds, who was with him at the time of the incident. Castile hands over the insurance document, just before the interaction quickly devolves into violence.
Yanez's not-guilty verdict sparked days of protests, including one on Friday that saw thousands of protesters and a shut down of I-94 for hours. Castile can be heard screaming as the shots ring out and says in agony "I wasn't reaching" as the officer begins to yell "fuck" again and again.
After the first shot, Mr Castile's body is thrown to the right.
A video showing the fatal shooting of a black Minnesota motorist by a police officer has been released days after the officer was acquitted.
At the time of the shooting, little over a year ago, Diamond Reynolds also live-streamed boyfriend Philando Castile bleeding to death in the vehicle.
"People are not protected against the police", she said Yanez's trial. He keeps his gun pointed at a dying Castile as he calls for backup and waits for other officers to arrive. He said: "Okay. Don't reach for it then". After an inaudible section, Castile says, "I'm not pulling it out". The city added that it was negotiating a voluntary separation agreement that would help Yanez transition into another career.