Dallas County Sheriff

Criminal Investigation

The Criminal Investigation Section provides various law enforcement activities in unincorporated Dallas County, which includes investigating criminal offenses, making arrests, preparing charges for prosecution, maintaining records, as well as criminal files and providing testimony as required. The Criminal Investigations Division assists local municipalities with investigations as requested. In addition, one authorized deputy is reimbursed by the Town of Sunnyvale based on their contract with the county to provide police services.

The Physical Evidence Section works very closely with the Criminal Investigation Section. PES investigators are the liaison to various crime labs (local, state and federal) and deliver the majority of Dallas Sheriff’s Office evidence to many of these labs. This section also conducts in-office investigations for other law enforcement agencies that bring evidence to examine and/or process.

At times officers secure crime scenes and use yellow crime scene tape to secure a perimeter. They use vehicles and other necessary methods to secure access to an active crime scene.

When available, these detectives are also sent to schools that deal with crime scene investigations or areas related to it. Field experience (i.e. patrol, warrants, etc.) is preferred from any officer seeking to transfer into PES.