Stewart, now 43, finds himself facing new controversy after his car struck and killed another driver, Kevin Ward Jr., 20, during a sprint car race Saturday at Canandaigua Motorsports Park in New York. Ward had exited his car Saturday night during a race to confront Stewart on the track when he was struck by Stewart's car.
Police say there are no charges pending against Stewart, that he appeared “very upset” over what happened and that he’s cooperating with authorities.
Following Ward’s death, Stewart withdrew from Sunday’s NASCAR race, the Cheez-It 355, at Watkins Glen International Raceway in New York.
The track tragedy drew new attention to Stewart’s previous incidents, run-ins that have made him one of racing’s most notorious and popular drivers.
After a 1999 crash with Kenny Irwin at Martinsville Speedway in Virginia, Stewart got out of his car -- and threw his gloves at Irwin before reaching into Irwin’s car.
Following a 2000 race at Watkins Glen, Stewart spewed expletives at Jeff Gordon.
He was accused in 2002 of assaulting a fan, but no legal action was taken.
He also punched a photographer after the 2002 Brickyard 400, drawing a $50,000 fine from his sponsor, Home Depot.
Stewart tossed his helmet at Matt Kenseth’s car during a 2012 race at Bristol Motor Speedway in Tennessee. “I don’t give a crap. The hell with the helmet,” he said later.
Stewart ran up to Joey Logano in 2013 and pushed him, before pit crews held the drivers back. Stewart was angry that Logano blocked him following a restart. "If he ever turns down across in front of me again, I don't care what lap it is, he won't make it through the other end of it,” Stewart said following the race.
Stewart also shared words with Kurt Busch following a 2013 race at Richmond International Speedway after their cars collided. Stewart stormed off following the race, leaving without talking to the media.
During a July 2013 race at Canandaigua Motorsports Park -- the same track where Saturday’s accident happened -- Stewart was involved in a crash that left Alysha Ruggles, 19, seriously injured.
A month later, Stewart broke his leg after crashing at a sprint car race in Iowa. The crash sidelined him for the rest of the 2013 racing season.
He recently returned to sprint racing, something Stewart considers a hobby. His passion for racing drew him to the smaller tracks such as Canandaigua Motorsports Park.