A police officer spent years reporting corruption inside his own department, through every proper channel available to him. He was ignored, again and again. Then he was shot in the face during a raid, and the fellow officers who were supposed to back him up never came.

His name was Frank Serpico.

He joined the New York Police Department in 1959, and by the mid-1960s was working plainclothes assignments across Brooklyn, the Bronx, and Manhattan.

There, he witnessed something systemic. Officers routinely accepted payoffs from gambling operations and drug dealers, a network of bribery woven through entire precincts.

He refused to take a cut.

For years, he reported what he saw up the chain of command, to superiors inside the NYPD and eventually to officials in Mayor John Lindsay's own office.

Here is the part that should make you angry. He was met, again and again, with concerned nods, vague promises of investigation, and no real action at all.

Eventually, alongside two colleagues, Paul Delise and David Durk, he took his story to a reporter, David Burnham of The New York Times.

On April 25, 1970, Burnham's front-page article, describing police corruption running into the millions of dollars, appeared in the Times.

The story forced Mayor Lindsay's hand. He created a special panel to investigate police corruption, which became known as the Knapp Commission.

Consider what came next, and how quickly it came. On February 3, 1971, less than a year after that article ran, Serpico was shot in the face during a drug raid at 778 Driggs Avenue in Williamsburg, Brooklyn.

The bullet severed a nerve and left fragments lodged near his brain.

His fellow officers, the men assigned to back him up that night, stayed in the hallway.

Many, including Serpico himself, have never accepted that this was simple bad luck.

He survived, permanently deaf in one ear, carrying shrapnel in his head for the rest of his life.

Later that year, the Knapp Commission opened public hearings. Frank Serpico testified before television cameras, describing in detail what he had witnessed and reported for years, to almost no response, before a single newspaper article changed everything.

Ask yourself what it took to finally make the department listen. Not years of internal reports. A front-page story, and a bullet.

Frank Serpico retired from the NYPD in 1972, on a disability pension from injuries he never fully recovered from.

In 1973, Al Pacino portrayed him in the film Serpico, winning a Golden Globe for the role, and introducing his story to millions of people who had never heard his name.

The Knapp Commission's findings led to real changes in how the NYPD investigated and oversaw its own officers, reforms that shaped internal affairs procedures for decades afterward.

Think about every conversation you have heard since about police whistleblowers, the so-called blue wall of silence, or officers who report their own colleagues and pay a professional price for it. Frank Serpico's name sits at the origin point of that entire conversation.

He spent the following decades as an outspoken advocate for police reform and whistleblower protection, still, in recent years, calling for his own shooting to be formally reinvestigated.

Frank Serpico told the truth for years before anyone in power was willing to listen. It took a bullet to his face to make them finally act on what he had been saying all along.