This is a story about double standards, half-truths, and hypocrisy. It is about a city, a political movement, and bad faith.

It started when Sean Schellenger got out of a car and crossed paths with Michael White in Rittenhouse Square on July 12.  When it was over, Schellenger was bleeding to death on the ground, and White was charged with his murder.  Those are the facts.

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But facts are fragile, fickle things these days.

As soon as the news broke that a white man had been killed by a black man, race drove the narrative.  Social media exploded with people excusing the knifing as "self-defense," even before the details were known.  People who reflexively blame police officers for "murdering" unarmed black men refused to believe that an unarmed white man was an innocent victim.  They argued that Schellenger was probably drunk, or that because he'd been a football player at Penn State, he was physically menacing to White.  There was no suggestion that anyone had touched White, or that Schellenger had a weapon.  It was enough that he was big, he might have been drunk, he was white, and he was with friends.

The "Big Drunk White Man" defense, like the gay panic defense, allows the aggressor to use his irrational hatred to try and avoid a criminal conviction.  It is "stand your ground" on steroids.  Unfortunately, here is where the double standards come in.

A few weeks after Schellenger was killed, a black man in Florida was shot to death by a white man who said he felt his life was in danger.  Video of that incident went viral, and it was clear that the shooter acted unreasonably, because the victim was in retreat when he was killed.  Virtually no one who saw that tape defended the shooter, who started a fight with the victim's girlfriend over a handicapped parking spot.

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Why, then, are some people willing to excuse the acts of Michael White as "self-defense" when no evidence has surfaced that his life was in danger?  They do it because they live in the city of Philadelphia, where race is often used as currency for political advantage.  District Attorney Larry Krasner made a big deal about the inequality in the criminal justice system when he was running for office, and some of the things he said made sense.  But the political movement that swept him into office was toxic, one that divided victims and aggressors along the color lines.  It stopped looking at people as individuals, and started regarding them as symbols.

So the family of a black police officer who was murdered while buying a birthday present for his son felt disrespected by a DA's office that never kept them in the loop.  Families of other black victims tell a similar story, that the DA's office seems more concerned for the rights of the accused than the plight of the abused.

And that is multiplied exponentially when the victim and the defendant are of different races.  The support that White has been getting is based in large part on his status as a young black man in a society that mourns Trayvon Martin.  But Michael White is not entitled to sympathy because Trayvon Martin is dead.  Sean Schellenger is also dead, because White allegedly killed him.

At least some people understand that.  I spoke with the Schellenger family this week, and they told me of the devastation they feel at the way Sean's killing is being treated in the press, and most especially by the DA's office.  Sean's uncle Jeff told me that "it has been incredibly difficult and heart-wrenching for our family to read and listen to the wild speculation around the facts in this case…we know, because the DA told us — Michael White was not being robbed while riding his bike home, he was not sitting on a stoop minding his own business, rather, he injected himself into a situation with complete strangers. When you deliberately stab someone with a 12-inch knife, you are intending to kill."

And echoing the refrain you often hear from the families of crime victims these days, he warns people to "look out for your own self-interests, because DA Larry Krasner will not do so."

Indeed, Krasner announced this week that White would be charged with third-degree murder, which makes him eligible for bail. Sean's life is valued at 10 percent of the $150,000 set for his alleged killer's release.

The irony in all of this is that, as his father, Mark, told me, "Sean spent so much of his life trying to lift up the African American community."

It is a bitter twist that Michael White allegedly killed a man who lived his life trying to help people just like Michael White.