SIO

Government & Politics abbreviation · Police

SIO
Stands forSenior investigating officer
CategoriesGovernment & Politics

SIO stands for Senior investigating officer, a police abbreviation.

UK police officer, usually a detective chief inspector or higher, in overall charge of a major investigation such as a homicide or kidnapping. The SIO sets lines of inquiry and makes key decisions.

Example: The SIO appealed for dashcam footage from anyone driving on the A road that night.

Usage notes

SIOs follow national guidance and record decisions in a policy file that can be scrutinized at trial. Major incident rooms use the HOLMES computer system to manage information in large inquiries. Specialist training and accreditation are required for the role.

More police abbreviations

  • POI – Person of interest
  • POST – Peace Officer Standards and Training
  • RMS – Records management system
  • ROR – Released on own recognizance
  • RTC – Road traffic collision
  • SFST – Standardized field sobriety tests
  • SO – Sheriff's office
  • SRO – School resource officer
  • SWAT – Special weapons and tactics
  • TASER – Thomas A. Swift's Electric Rifle
  • TWOC – Taking without owner's consent
  • UC – Undercover officer

See all 84 police abbreviations →