The crash raised several questions: Will Ward's death cause drivers to think twice about on-track confrontations? Did Stewart try and send his own message by buzzing Ward, the young driver, only to have his risky move turn fatal? Or did Ward simply take his life into his own hands by stepping into traffic in a black firesuit on a dark track?
The only one who may have that answer is Stewart.
David S. Weinsten, a former state and federal prosecutor in Miami who is now in private practice, said it would be difficult to prove criminal intent.
"I think even with the video, it's going to be tough to prove that this was more than just an accident and that it was even culpable negligence, which he should've known or should've believed that by getting close to this guy, that it was going to cause the accident," he said.
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The sheriff renewed a plea for spectators to turn over photos and videos of the crash. Investigators were reconstructing the accident and looking into everything from the dim lighting on a portion of the track to how muddy it was, as well as if Ward's dark firesuit played a role in his death, given the conditions.
Driver Cory Sparks, a friend of Ward's, was a few cars back when Ward was killed.
"The timing was unsafe," he said of Ward's decision to get out of his car to confront Stewart. "When your adrenaline is going, and you're taken out of a race, your emotions flare."
It's often just a part of racing. Drivers from mild-mannered Jeff Gordon to ladylike Danica Patrick have erupted in anger on the track at another driver. The confrontations are part of the sport's allure: Fans love it and cheer wildly from the stands. Stewart, who has a reputation for being a hothead nicknamed "Smoke," once wound up like a pitcher and tossed his helmet like a fastball at Matt Kenseth's windshield.
"I've seen it many times in NASCAR, where a driver will confront the other one, and a lot of times they'll try to speed past them. And that's what it appeared to me as if what Tony Stewart did, he tried to speed past Ward," witness Michael Messerly said. "And the next thing I could see, I didn't see Ward any more. It just seemed like he was suddenly gone."