Senior trooper is a rank used by several state police agencies within the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 and in some world militaries.

It is the third class in the progressive series of state trooper ranks. It is a step below master trooper

Master Trooper

Master trooper is a rank used by several state police agencies within the United States and in some world militaries.In particular, in the Louisiana State Police, in the United States, it is a rank below sergeant, yet above senior trooper. The insignia for this rank consists of a gold colored 'MT'...

, yet above trooper first class

Trooper First Class

Trooper first class is a rank used by several state police agencies within the United States and in some world militaries.In particular, in the Louisiana State Police, it is a rank below senior trooper, yet above trooper. The insignia for this rank consists of a gold colored 'TFC' collar pin worn...

. For some agencies, the insignia for this position consists of a gold colored 'ST' collar pin worn on the wearer's right lapel while others bear a 'senior trooper' plate that is located below their nametag. The title of address is trooper or senior trooper.

Responsibilities

Senior troopers take on the responsibility to use preventative measures in dealing with accidents and crime, enforce the law, conduct highway patrol, investigate, and perform related administrative duties in order to protect citizens, visitors, public highways, and property of the State or Commonwealth. Senior troopers also provide mentoring, guidance, and training to newly assigned troopers. They have jurisdiction in all parts of the State or Commonwealth they serve and carry a weapon.

Requirements

Senior troopers are required to be knowledgeable on criminal and traffic laws, skilled in the use of firearms and operation of an issued vehicle.

Career Progression

Troopers who complete ten (10) years of satisfactory or exceptional service are promoted to the rank of senior trooper. However, it is possible for a trooper to become a senior trooper without 10 years of experience. Consideration for movement to senior trooper, master trooper

Master Trooper

Master trooper is a rank used by several state police agencies within the United States and in some world militaries.In particular, in the Louisiana State Police, in the United States, it is a rank below sergeant, yet above senior trooper. The insignia for this rank consists of a gold colored 'MT'...

, and senior special agent is based on (1) years of experience, (2) performance evaluation (determines eligibility and used in the event of a tie), (3) discipline, (4) weight control, and (5) educational achievement (used only in the event of a tie). Becoming a senior trooper is not a rise in rank but does include a pay raise.

Other

Usage in other agencies or countries may vary.
In the United States, state agencies are referred to state police

State police

State police are a type of sub-national territorial police force, particularly in Australia and the United States. Some other countries have analogous police forces, such as the provincial police in some Canadian provinces, while in other places, the same responsibilities are held by national...

 or highway patrol

Highway patrol

A highway patrol is either a police unit created primarily for the purpose of overseeing and enforcing traffic safety compliance on roads and highways, or a detail within an existing local or regional police agency that is primarily concerned with such duties.Duties of highway patrols or traffic...

.