Prof. David Collum ’77, chemistry, has come under fire from both students and administrators for a series of Thursday night tweets defending police officers that pushed and severely injured an elderly man. In a graphic film that has since become viral, a 75-year-old white man could be seen lightly brushing up against Buffalo police — who donned heavy tactical gear — as he approaches them. In response, two of the cops shoved the man, causing him to fall and hit his head. As the man lays bleeding and unresponsive, over a dozen officers appear to simply walk away, failing to...