K-9 unit introduces the chihuahua as the new international police working dog nadia April 1, 2016 chihuahua news the livermore police k-9 unit introduced a chihuahua named ‘mocha’as their new team member today. in this video, mocha demonstrates “tactical rolls” and patrols the downtown with an officer … april fools! Follow Famous Chihuahua on Istagram share this on social media!