Sheridan County, Montana Sheriff’s Office and 911 Communications Center is officially live!!!! Sheridan County Sheriff’s Office and 911 Communications Center serves over 3,700 citizens and 1706 square miles. They are supported using RIMS CAD/RMS, InCustody Jail Management System, NCIC/Montana CJIN State Switch, and Montana IBRS (Incident Based Reporting System). Welcome to the RIMS Family!!!