DOUGLAS COUNTY, Colo. (CBS4) – An investigation into the death of a man who shot and killed a Douglas County sheriff’s deputy has been finalized.

Matthew Riehl (credit: CBS)

The report finds the officers who shot and killed Matthew Riehl acted lawfully.

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Riehl shot Deputy Zack Parrish on New Year’s Eve at Riehl’s apartment.

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(credit: Douglas County Sheriff’s Office/CBS4)

The gunman also injured other deputies and a police officer along with two neighbors.

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(credit: Douglas County Sheriff’s Office)

The investigation reveals deputies reasonably feared for their lives when they shot Riehl. It adds he posed a deadly threat to law enforcement and the community.