The teen car passenger who filmed himself encouraging his friend to mow down a retired police officer riding his bike through Las Vegas was arrested Tuesday, officials announced. The unidentified minor and the teen driver — who was already in custody — are both facing murder charges in the disturbing hit-and-run death of 64-year-old Andreas Probst last month, Las Vegas officials said at a press conference. “It’s a complete lack of conscience on a part of it and the worst part about it in the video is you hear that everything was intentional,” Las Vegas Metropolitan Police Department Detective Lieutenant...