REDWOOD CITY -- Jurors heard closing arguments Tuesday in the trial of a truck driver involved in a crash that killed 9-year-old Tyler Fahy outside a San Mateo Mollie Stone's grocery store in 2008.

While there was no disagreement among attorneys that the crash was tragic, prosecutor Michael Wendler argued this afternoon in the trial against 44-year-old Carlos Siordia that it was tragic because it was avoidable.

"Mr. Siordia failed to maintain control of his truck," Wendler said. "He acted in a negligent manner."

Siordia was driving a construction truck that plowed through the intersection of Olympic and 43rd avenues in San Mateo and struck a sport utility vehicle at about 1:15 p.m. on Sept. 22, 2008.

Both vehicles then traveled into the Mollie Stone's parking lot and hit seven other cars and a pedestrian.

Fahy, who was a passenger in the SUV, died at the scene. His mother and two other women were injured.

Siordia has maintained that the brakes on the truck didn't work, and his defense attorney John Elworth said during his closing arguments that Siordia was consistent in his interviews with police.

"The truck's brakes were working 10 minutes prior (to the crash)," Elworth said. "Mr. Siordia didn't know there was anything wrong with the truck."

Siordia has been charged with misdemeanor vehicular manslaughter, which could land him in jail for up to a year in county jail if convicted.

During his closing arguments, Wendler pointed out two possible theories to the jury as to what Siordia is guilty of.

The first theory is that Siordia committed "an unlawful act with ordinary negligence" causing death, and the second is that Siordia committed an infraction, such as speeding or coasting, causing death.

Elworth, however, told the jurors that the prosecution's inability to pinpoint a specific crime that occurred is what makes his client not guilty.

"The district attorney is coming up with any allegation about Mr. Siordia and hoping it will stick," Elworth said.

Siordia is out of custody on a $25,000 bail bond.