Johnson was killed by a state trooper who found him sleeping in his vehicle, which was parked at the top of an on-ramp on Loop 101.
Phoenix Mayor Kate Gallego and Tucson Mayor Regina Romero joined over a dozen mayors across the country asking the Trump administration not to send federal agents to American cities.
An analysis of over 50,000 criminal cases found that Black and Latino defendants are given longer sentences and higher fines than their white counterparts.
Lawmakers say Trump's call for "an overwhelming law enforcement presence" will only lead to more violence against protesters.
'Operation Crystal Shield' was announced to combat meth trafficking in Arizona, just days before police pulled off a $12 million drug bust.