Investigators are seeking a vehicular homicide charge against the father of a 4-year-old boy who died near Mount Spokane last summer.

Gerrin P.R. LaFleur died Aug. 19 during a family firewood-gathering trip in the foothills near North Wallis Road and East Elliot Road.

His father, Lester C. LaFleur, told authorities the boy fell from atop his parked 1985 Ford F-250 pickup.

But investigators received conflicting reports of what happened and searched the truck for hair fibers, fingerprints and other evidence to understand the circumstances surrounding the death. An autopsy said the boy died of a bruised and cut right lung, according to court documents.

Spokane County sheriff’s Detective David Thornburg now believes enough evidence has been found to support a vehicular homicide charge against the father.

Thornburg said the boy’s injuries appeared to have been caused when the truck was moving.

The Spokane County Prosecutor’s Office is reviewing the detective’s recommendation.

LaFleur, 35, declined to comment through his brother-in-law, Jeremiah Donier, who said the family is being treated unfairly.

“We want the whole community to know that we certainly do care that Gerrin passed way. We feel that it was a tragedy,” Donier said. “People have not talked about it correctly.”

LaFleur called 911 while driving to a fire station and said he thought his son was dead.

One of Gerrin’s older sisters said a branch pulled the boy out of the truck when it was moving.

Another family member said the boy had unbuckled his seat belt and climbed out of the truck.

Detectives found two child-size boot marks on the top of the driver’s side rear bumper.