A professional drag racer who accidentally killed six spectators when his car spun out of control during a parade pleaded guilty to misdemeanor charges Thursday and will not serve jail time.

Troy Critchley, 38, an Australian now living in Texas, pleaded guilty to 28 misdemeanors, including reckless assault, and was sentenced to 18 months probation.

Felony charges of vehicular homicide and aggravated assault were dismissed under a plea agreement approved by Judge Weber McCraw.

Critchley's powerful dragster spun out of control and smashed into spectators during a June 2007 car-show parade and fundraising festival in Selmer, a small town 80 miles east of Memphis.

He apologized to the victims and their families Thursday.

"I ask for the families' forgiveness and prayers, and I will pray for your families and loved ones," Critchley said.

The driver said he did not intend to hurt anyone and was in Selmer hoping to help children by raising money for a nonprofit group called Cars for Kids Southern Style Inc., which sponsored the event.

The crash occurred while Critchley was performing a stunt called a burnout on a public street lined on both sides with onlookers unprotected by barriers.

With its engine roaring and spinning tires smoking, his dragster crashed into the crowd. Some spectators were tossed into the air while others were trapped beneath the car.

Aside from the six people killed, 22 others were hurt, many seriously.

Darla Griswell, the mother of two teenagers who died, cried as she testified that her family will never be the same.

She said charity founder and parade organizer Larry Price and the city officials who allowed the event also are responsible.

"You have completely ruined our lives," Griswell said. "Does your mind ever think about anything else? Mine won't."

She said after the hearing that she accepts Critchley's apology.

Price said outside the courtroom that he doesn't understand why he would be blamed.

Thursday's testimony did not provide any more information on how the accident happened. The Tennessee Highway Patrol said it will release the results of its investigation now that the criminal case is over.

No one associated with Cars for Kids or with the town of Selmer, which approved the event, was charged with criminal wrongdoing.

Defense lawyer Robert Hutton said a trial for Critchley would have raised legal questions about "whether you can even have a criminal prosecution for something that the government itself sets up."

Prosecutor Michael Dunavant said the plea agreement opens criminal investigation records to victims who have filed lawsuits seeking millions of dollars in damages from Critchley, Cars for Kids and Selmer.

Critchley "has expressed continued remorse and concern for the victims," and the plea agreement makes it unlikely he will engage in such car-show events again, Dunavant said in a statement.

After the crash, town officials set tighter rules for such events and denied a 2008 parade permit for Cars for Kids. The organization held its festival without a parade or burnout demonstration.