Nathan Sweeney, 44, of DeKalb, was charged with reckless homicide and DUI causing death.
Illinois State Police said he was under the influence of drugs, when his truck ran off the road and hit Deputy Christina Musil's squad car.
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On Monday, a judge ordered his release under conditions of the SAFE-T Act and Sweeney was released from Ogle County Jail Monday afternoon, officials said.
RELATED | Truck driver charged with DUI, homicide in crash that killed DeKalb Co. deputy Christina Musil
Musil served in the sheriff's office for five years and also served in the Army National Guard. She leaves behind three young children.