When the Eagles clinched their first-ever Super Bowl victory on Sunday — that will always feel wild to say — my friends and I joined the joyful, inebriated throngs in a spontaneous pilgrimage to Philadelphia's City Hall. And at Thursday's championship parade, you'd likely hear many of the same full-throated chants that we heard right after the win. The Eagles fight song, obviously. Some colorful suggestions for what the vanquished Tom Brady could do to himself, also obviously. And then another, more charged exhortation: Free Meek Mill!

Meek Mill, whose real name is Robert Williams, is one of the highest profile rappers ever to come from Philly. And when the Eagles ran out onto the field on Super Bowl Sunday, they did so over Meek's "Dreams and Nightmares," a song that they had been playing at the team's practices since the playoffs began.

The Eagles picked "Dreams and Nightmares" as their hype song for functional reasons — it's a song about overcoming long odds and constructed to make you feel like you can run through a brick wall — but there was something political about the choice as well. Meek had been on probation for nearly a decade stemming from a gun conviction in 2008, when he was 21. Then last year, he was sentenced to two to four years in prison for violating those probation terms. He had a long and spotty probation history, with a grip of failed drug tests and missed court appearances, some of which extended his probation. After his sentencing, several Eagles players attended a rally protesting the decision.

None of which is especially remarkable for people on probation, which is exactly why he has become a poster boy for critics of the criminal justice system. They point out that failing a drug test, or driving outside of the county, or failure to hold down a job are not jailable offenses for anyone but probationers. (For Meek, the violations that finally got him sent to prison were an airport fight and a reckless driving charge for popping a wheelie on a motorcycle in a video he posted to Instagram, even though charges in both instances were dropped.)

There are many, many people of far less means than Meek Mill in similar binds — ostensibly free, but constrained by their probation terms. (Imagine trying to find a job or public housing with a felony conviction and restrictions on where you can travel.) There are currently more Americans on probation than on parole, in prison or in jail combined — and the racial disparities in probation are as stark as they are in every other part of our criminal justice system. A 2014 study by the Urban Institute found that across four different counties in the U.S.,black probationers were 55 percent more likely to have their probation revoked than white people were.

Meek's story comes just as Philadelphia rethinks its approach to crime and punishment. For decades, Philly's district attorneys have been notoriously tough on crime, which is one reason the city currently has the highest incarceration rate of the 10 largest U.S. cities. But the current mayor, Jim Kenney, ran on a platform of police reform and getting rid of stop-and-frisk. And the new DA, Larry Krasner, is a former defense lawyer who made his name suing the police department, wants to abolish cash bail and was championed by activists from Occupy Philly and Black Lives Matter. (As you might imagine, that has not always engendered them to the city's police and prosecutorial brass.)

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