That one simple question is the one that has been swirling around in my head since I first heard of the horrific tragedy that snuffed out the life of a young woman from Chester County in a road-rage incident.
What could possibly make someone do something so abhorrent, so senseless, as to pull out a gun and shoot another driver?
We still don't know. A preliminary hearing for the man charged in this brutal killing was continued yesterday.
In the meantime, the friends and family of Bianca Roberson continue to mourn the senseless loss of a promising young life.
Roberson, a recent graduate of Rustin High School in West Chester, was headed to Jacksonville University in Florida in just a few weeks to start college.
She was apparently jockeying for position with another driver on a portion of Route 100 in West Goshen where the road goes from one lane down to one. Both drivers were involved in what police describe as a "cat and mouse" game.
Then the unthinkable happened. The other driver pulled out a gun and shot Bianca in the head, killing her instantly.
The story not only captured national attention, it also became a much more intense story for us here at the Daily Times when we learned the man charged in her shooting death was from Delaware County.
David Desper, of Trainer, now faces charges of first- and third-degree murder.
As we always do in such stories, we tried to find out what we could about Desper.
We didn't learn much. Not many people were talking about him.
We did not do this in an attempt to paint him in any kind of less harsh light. What he is charged with doing is abhorrent.
We ran a photo of him from his high school yearbook that also offended some readers. That also is something we often do as we dig into the background of people charged with serious crimes.
We are not looking for - or offering - any excuse for what he is charged with doing.
We don't want to see him acquitted - as some have charged.
We want only justice for Bianca Roberson, and an explanation as to how a person could possibly be capable of doing something so heinous.
Bianca's father, Rodney Roberson, has stated that the family intends to attend the preliminary hearing and has said he wants to ask him a simple question: "What gave you the right? What made you think it was all right to take my daughter."
I don't blame him a bit.