The Criminal Investigations Division is under the command of Captain Tommy Erwin. The primary function of the division is to investigate reports of criminal activity after a crime has been reported to this department. The Criminal Investigations Division also conducts proactive investigations and covert operations in an attempt to deter criminal activity before it occurs.

When you report a crime to the Martin Police Department, a patrol officer will respond to the location of the crime and complete an incident report detailing the crime. The incident report will then be forwarded to criminal investigations on the next business day for review.

Division Contacts:

Captain Tommy Erwin

731-587-5355 ext 2251

Lieutenant Robby Hatler 

731-587-5355 ext 2226

Investigator Sarah Turner

731-587-5355 ext 2248

Investigator Scott Diehl

731-587-5355 ext 2247


Sarah Turner (Investigator)

Sarah was hired June of 2014 as a patrol officer. She is a graduate of the 3rd session National Forensic Academy Collegiate Program. She graduated from The Tennessee Law Enforcement Training Academy October of 2014. She graduated from the University of Tennessee at Martin in the fall of 2016 with a B.S. in Interdisciplinary Studies. Sarah became an investigator in August of 2019.

Scott Diehl (Investigator)

Scott started his Law Enforcement career with Martin PD on February 12th 2003. He has received training in many areas. During his time with Martin PD, he has served in many capacities. In 2007 Scott went to work for the Governor’s Highway Safety Office where he received additional Law Enforcement training. On February 14th 2015 Scott returned to Martin PD. Since returning he has continued training in several areas. He is one of the department’s Crash Reconstructionist, Firearms Instructors and has served on the Special Response Team. On June 1st 2021 he was promoted to Investigator and was assigned to the Criminal Investigations Division where he currently serves. Scott graduated high school in 1992, following graduation he served in the US Navy as an Aviation Electronics Technician from 1992-1996. After service he enrolled at the University of Tennessee at Martin the Fall of 1997. While attending UTM he was a member of the Men’s Rodeo Team. Scott studied Agriculture Science and graduated in 2001.