2:52 PM PT -- According to the crash report -- obtained by TMZ -- it details Kevin leaving the scene after the accident while Black and Broxterman remained trapped.
The report also lists the extensive bodywork Kevin had done to the Barracuda ... including adding a 6.4L Hemi V-8 engine, sport tires as well as custom gauges and graphics. It also mentions the vehicle was without an anti-lock braking system.
As for the seat belts, the report says, "There were fold and crease marks on the belt surfaces consistent with being folded and tucked into the seats and no indicators of occupant loading were present." Cops say even if the belts were worn at the time of the crash, "They were being worn improperly due to excessive slack in the belts."
The report says Broxterman was pinned between the top of the right passenger seat and the collapsed roof of the vehicle, with her head facing the windshield. The report also notes the car was, "not outfitted to carry rear seat passengers." Kevin replaced the backseats with plastic storage boxes.
Kevin Hart's car crash was caused by the driver operating the vehicle in a reckless fashion ... this according to the California Highway Patrol, which has just completed its report on the accident.
Law enforcement sources tell us ... Kevin's 1970 Plymouth Barracuda crashed because driver Jared Black gunned the engine and lost control. The car had incredible power with a 720-HP engine. We're told the sudden acceleration and loss of control caused the vehicle to go into a spin and it ended up crashing through a fence and into an embankment.
According to our sources, the report says none of the 3 people in the car were wearing seat belts. As we reported, the Barracuda did not have safety harnesses, but now it's not an issue since they weren't wearing any safety device.
Our sources say the vehicle did not have any mechanical issues. It was purely driver error -- willful or wanton disregard for people or property.
Although the CHP report lays the blame at Jared's doorstep, Kevin doesn't seem to harbor bad feelings. He tells TMZ through his lawyer, Andrew Brettler, "I have nothing but love for Jared and wish him and Rebecca a speedy recovery."
As we first reported ... CHP disassembled Kevin's 1970 Plymouth Barracuda to determine the cause of the crash, stripping it down to nuts, bolts and metal pieces to evaluate the evidence and write a report.
Jared suffered similar injuries to Kevin, who was riding shotgun. Jared's fiancee, Rebecca Broxterman, was in the backseat, but she escaped the crash with minor pain. All 3 have lawyered up, and everyone's expecting a big lawsuit.
You'll recall ... a witness within earshot of the crash told us they heard tires screeching before hearing a loud boom.
And, multiple sources tell us ... there will be multiple lawsuits stemming from the crash.