His policies were credited with preventing serious rioting in Philadelphia during the summer of 1967, while cities with a similar proportion of Black Americans, such as Detroit and Newark, were affected. The next year, Chicago, Baltimore, and Washington, D.C. all experienced significant riots in April 1968 after the assassination of Martin Luther King, Jr., and a contemporary analysis by Drew Pearson gave credit to "one of the toughest cops in the USA", Commissioner Frank Rizzo, and his "well integrated" police force for preventing similar rioting in Philadelphia.