(Reuters) - Three-time NASCAR champion Tony Stewart has been cleared by a grand jury investigating a dirt-track incident in upstate New York in August that killed a young driver, a county prosecutor said on Wednesday.
Stewart, 43, one of the biggest names in auto racing, struck and killed Kevin Ward Jr., 20, during a non-NASCAR sprint-car race on Aug. 9 on a dimly lit part of the Canandaigua Motorsports Park track, about an hour's drive west of Syracuse.
Ontario County District Attorney Michael Tantillo said authorities submitted possible charges of manslaughter in the second degree and criminally negligent homicide against Stewart, and the grand jury "determined that there is no basis to charge Tony Stewart with any crimes."
Toxicology tests indicated that Ward was under the influence of marijuana that night, at levels "enough to impair judgment," Tantillo told a news conference. He said Stewart was not tested, but he was interviewed that night by a certified drug recognition expert, who did not find any impairment.
Stewart said in a statement: "This has been the toughest and most emotional experience of my life, and it will stay with me forever."
The Ward family said the "matter is not at rest and we will pursue all remedies in fairness to Kevin."
"All other vehicles were reducing speed and not accelerating except for Tony Stewart, who intentionally tried to intimidate Kevin by accelerating and sliding his car toward him causing this tragedy," the family said in a statement.
Authorities maintained early in the investigation there was no evidence of criminal behavior by Stewart, but refrained from clearing him while they tried to determine if he hit the throttle as he approached Ward.
Tantillo said the grand jury saw accident reconstructions, reviewed photographs and two video recordings of the incident, heard from witnesses and was presented with other evidence. It deliberated less than an hour before deciding on Wednesday not to indict Stewart.
Stewart and Ward bumped cars during the race and the collision sent Ward into an outside retaining wall while Stewart remained in the race. Ward jumped from his car in an apparent attempt to confront Stewart during the ensuing caution period.
When Stewart's car came around on the next lap, Ward, while in the middle of the track, pointed at Stewart. Stewart's vehicle struck Ward, throwing him 50 feet (15 meters). Ward was pronounced dead at a hospital near the track.
Tantillo said the videos showed no "aberrational driving" by Stewart, whose car he said was going fairly straight until it veered up the track after striking Ward.
Stewart, who had often driven in non-NASCAR races, went into seclusion for the next three weeks. He returned to NASCAR on Aug. 31 but has not finished in the top 10 since his return and has been winless this year.
NASCAR introduced rules following the fatal incident that forbid drivers from getting out of their cars during caution periods until permitted to by a track safety official.
Reporting by David Bailey in Minneapolis; Additional reporting by Lewis Franck; Editing by Peter Cooney and Eric Beech