An Otter Tail County deputy is charged with misconduct and driving under the influence of fentanyl during a high-speed chase that ended in a deadly crash in Fergus Falls last October. Deputy Kelly Backman was pursuing a minivan driven by a man in a drug investigation when the van slammed into a car, killing 72-year-old Steve Christianson and his 71-year-old wife Diane, both from Fergus Falls. The complaint says Deputy Backman tested positive for fentanyl and also a prescription anti-anxiety medication.