Yes and yes. https://medium.com/waymo/recognizing-the-sights-and-sounds-of-emergency-vehicles-8161e90d137e https://medium.com/waymo/recognizing-the-sights-and-s

Yes and yes. https://medium.com/waymo/recognizing-the-sights-and-sounds-of-emergency-vehicles-8161e90d137e https://medium.com/waymo/recognizing-the-sights-and-sounds-o... Though one can easily imagine a system designed to prevent the latter. Preventing hijackings is more complicated than that though, since an autonomous vehicle will stop for anyone who gets in its way, not just police officers. The array of cameras, lidar sensors, etc each car comes with is probably a fairly decent deterrent against that threat already though.