As the investigation into the fatal New Year's Eve shooting involving a Missoula Police Officer continues, a department official provides the policy on officer-involved shooting investigations.

Public Information Officer Travis Welsh said there are several aspects to the investigation.

"Generally, there's an external investigation typically completed by an outside agency," Welsh said. "There's also an internal investigation that goes on at the same time that is conducted by the Office of Professional Standards here at the Missoula Police Department. Both of those investigations are reviewed by the Chief of Police who then meets with the County Attorney to discuss any findings."

Welsh said there is an added investigation in a fatal shooting.

"In the case of a death, there is also a coroner's inquest," he said. "After those findings are reviewed, a determination is made as to the officer's fitness to return to duty and a schedule for that to occur."

Welsh said one final step is necessary before an officer involved in a fatal shooting is allowed to return to duty.

"After the chief has made a review, internally, the Missoula Police Department holds a deadly force review board, which is made up of officers from the department who review these incidents, and then consider and make recommendations to the Chief of Police which may reduce the possibility for the need to use deadly force in situations such as these, and in the future," Welsh said.

Corporal Paul Kelly is on paid administrative leave after the fatal New Year's Eve shooting of Kalieb Williams, 20. Police reports indicate that Kelly fired one shot into Williams' vehicle after Williams refused repeated demands that he stop strangling his female hostage.

Deputy County Attorney Jason Marks has indicated to KGVO News that he has received the investigative files from both the police and sheriff's department and is currently reviewing them. An announcement as to the date for a coroner's inquest is forthcoming.