Vancouver police say they have decided against recommending criminal charges in the death of a 23-year-old woman who fell out of a party bus in January.

Police say Chelsea James lost her balance and stumbled into the stairwell against the pneumatic passenger door, which opened and she fell out of the bus.

She was pronounced dead at the scene.

VPD say their collision investigation unit and commercial vehicle unit conducted an extensive investigation and brought in engineers to assist with mechanical inspections of the bus.

Police say it was determined that a mechanical malfunction and low operating pressure with the pneumatic door were the main contributing factors in the death.

No criminal charges will be recommended but the owner and the driver of the party bus have been fined under the Motor Vehicle Act and are still subject to potential civil action.