Police investigators at the scene of an officer-involved shooting on Sunday. (CBS) Pleasanton Police investigators at the scene of a deadly officer shooting, July 5, 2015. (CBS)

PLEASANTON (CBS SF) — Attorneys for the family of a man shot and killed by police during a confrontation outside a Pleasanton auto dealership earlier this month have accused the Police Department of covering up the facts of the shooting.

In a statement released Thursday, the law firm Geragos & Geragos accused the department of inconsistencies in its accounts of the shooting and obstruction in responding to questions about the case.

Police last week released a lengthy account of the July 5 confrontation outside Specialty Sales Classics, a car dealership specializing in antique and exotic cars at 4321 First St.

Initial police accounts said that 19-year-old John Deming Jr. was found outside the dealership when police arrived at about 2 a.m., but the revised account said he was inside but visible through the dealership’s large glass windows.

Police said he was acting threateningly and erratically, throwing a 50-pound floor jack through the window. Officers tried to subdue him with beanbag rounds but missed.

The officers went in after Deming with a dog, and attorneys for the family said police dispatch records indicate that only 22 seconds passed between officers entering the business and Deming being shot.

According to police, once officers entered they found Deming in a back room. He escaped out a broken window and was chased by Officer Daniel Kunkel. Deming then turned to fight Kunkel, knocking him to the ground and punching him repeatedly in the head.

Kunkel twice used a Taser on Deming but that failed to subdue him, so he shot him once. But Deming continued the attack even then and finally Kunkel shot Deming twice more, including once in the face.

Police said Deming continued to resist officers as they tried to handcuff him. Kunkel was knocked unconscious, according to the police account.

The family’s attorneys said it is impossible for the confrontation as described to have lasted only 22 seconds. They also questioned why Kunkel was reportedly released from the hospital later that day given the severity of the described attack.

Also unclear is whether Kunkel was wearing a body camera at the time of the shooting and captured the incident on video. The firm has accused police of inconsistent statements in this regard, at first saying the incident was captured on video but later saying it was not.

The attorneys said the Police Department then started a campaign of “character assassination” against Deming, searching his mother’s home for evidence of drugs and burglaries. During the search, officers handcuffed his mother and held her at gunpoint while refusing to tell her where her son was, according to the attorneys.

Thursday, the attorneys said Pleasanton police also attempted to interrogate Deming’s grandmother and recent barbecue guests to the family’s home.

The family retained the law firm of Geragos & Geragos shortly after the shooting. The Southern California-based firm has represented numerous celebrity clients, including Chris Brown and Michael Jackson.

The family has also retained an independent forensic pathologist who conducted an autopsy on Deming’s body last weekend and is preparing his findings, according to the attorneys.

Deming was the son of an Oakdale reserve police officer and recently graduated from Piedmont Hills High School in San Jose, where he was a football player. A memorial for him will be held at the school at 8 p.m. Friday.

Pleasanton Police Chief Dave Spiller told CBS San Francisco Thursday afternoon his department is still conducting its investigation and it would be inappropriate to comment while the investigation is ongoing.

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