Electra Glide in Blue (1974)

A police officer of short stature assigned to patrol the Arizona desert by motorcycle, John Wintergreen (Robert Blake) hopes to break out of his rookie status and join the homicide department. When Wintergreen catches a break and gets an opportunity to work on a murder case, he jumps at the chance. Meanwhile, the lawman becomes disillusioned with many of his peers and the way that they harass hippies, and this ongoing conflict has a major effect on Wintergreen's life.