Above: Diamond Reynolds, second from left, reacts to a speaker outside the Governor’s Mansion on July 7 in St. Paul, Minn. Reynolds live-streamed the aftermath of an encounter in which her boyfriend Philando Castile was shot by a police officer on July 6. (Stephen Maturen/Getty Images)

The rise of cellphone video throws into sharp relief a question that has always dogged police fiction: Who’s telling the truth about what the police do?

Is it a reality show like “Cops,” which, for all its manufactured quality, does capture the pathetic nature of certain classes of crime, the relentless dullness of police work and the craving some officers have for action? Is it “Dragnet,” with its mythic, and mythical, version of policing? Is it “The Wire,” informed by Simon’s years of reporting and Burns’s years of policing and teaching? Is it Joseph Wambaugh, who for a brief period in the ’70s captivated Americans not with police procedurals about how, as he puts it, “the cop acts on the job,” but with searing portraits of how “the job works on the cop”?

All these storytellers have contributed their own pieces to our understanding of one of America’s most complex professions. And given the times in which they told their stories, the power of the police in that moment and their levels of personal courage, they told the stories they were capable of telling and that they had the freedom to tell.

“Jack Webb wanted to make his shows grittier and more true to life, psychologically, showing all the damage that police work does to cops,” Wambaugh remembered. “The premature cynicism, the constant psychological bombardment from the worst of people and from ordinary people at their worst. All of that, he wanted to do some of that. But he couldn’t if he wanted the cooperation that he always got from the LAPD.”

Webb didn’t have the fortitude, or the personal appetite for risk, to walk away from the LAPD. More than half a century later, Simon’s willingness to leave Baltimore ensured that he would be able to shoot the story that he wanted on the streets where he meant for that story to take place.

When Simon testified before the Baltimore City Council about a resolution intended to counteract the negative image of Baltimore depicted in “The Wire,” he made a larger point that might have seemed laughable or even dangerous, back when Hollywood was young, and mayors and police departments treated pop culture as a potential source of crime.