EL CAJON, Calif. -- A Jamul contractor who fatally shot a young man in an SUV on a rural East County roadway made a "huge error in judgment," a prosecutor told jurors Wednesday, but a defense attorney said the man was acting reasonably in self-defense in the wake of a series of thefts from his property.

Joseph Robert "Bob" Orlosky, 57, is charged with voluntary manslaughter, two counts of attempted voluntary manslaughter and shooting into an occupied vehicle in connection with the Dec. 1, 2006, shooting that took the life of Charles "Chuck" Crowe.

Deputy District Attorney Jeff Dusek told the seven-woman, five-man jury that Orlosky made a "huge mistake" and a "huge error in judgment" when he fired on the Jeep Cherokee with an AR-15 rifle.

Crowe and the driver, David Hurley, were taking a third man, Hector Monget, home that night when they decided to drive up a dirt road off Skyline Truck Trail so they could check property sale signs and "get sideways" -- spinning out in the dirt, Dusek said.

Upon returning from the end of the dirt road, they were confronted by the defendant, who unloaded at least 10 shots into their vehicle, Dusek said.

Most hit the tires, but one shattered the rear window and struck the 23-year-old Crowe, a married father.

"Chuck Crowe was shot in the back of the head as they were driving for help," Dusek said.

But defense attorney Paul Pfingst told jurors that his client, a heavy equipment contractor who stored the tools of his trade on his 163-acre property, had been plagued by a series of copper thefts in the months before the shooting.

Two weeks before Crowe was killed, he detained at gunpoint three such thieves, who were eventually arrested by sheriff's deputies and later convicted, Pfingst said.

The Sheriff's Department was aware that people were "stealing any copper that wasn't nailed down," Pfingst said.

The lawyer said that the trial will cover about four to five seconds of the life of Orlosky, whom he described as a hard-working business owner and married father of four.

With his birthday coming up and a deal about to be struck on producing from a mine near Yuma, Orlosky was certainly not planning on killing anyone, he said.

Monget suffered a minor elbow wound in the shooting but Hurley was unhurt. There was no stolen copper or tools in their vehicle, Dusek said.

Orlosky was originally charged with murder and attempted murder, but he was acquitted last year.

The retrial is expected to last at least a month in the El Cajon courtroom of Judge Louis Hanoian.