In Texas, the duty of performing an inquest, in most counties, falls on the Justice of the Peace, as stated in Chapter 49 of the Code of Criminal Procedure. 

Some counties have chosen to employ specially trained individuals to assist with the inquest load. These individuals are called death investigators. They are paid by the commissioners court and serve at their will. A death investigator works on an inquest when requested by the Justice of the Peace. A finalized report containing activities, findings, and conclusions shall be provided to the Justice of the Peace within eight hours of the death being investigated by a death investigator. 
Code of Criminal Procedure Art. 49.23.

The Midland County Office of Death Investigators was established by the Commissioners Court on October 1, 2019, under the direct supervision of the four Midland County Justice of the Peace. The fundamental duty of the death investigators is to assist the person conducting an inquest to investigate the time, place, and manner of death and complete a report of the death investigator’s activities, findings, and conclusions to the Justice of the Peace or other person conducting the inquest.

The official definition of an inquest from Texas law is: “an investigation into the cause and circumstances of the death of a person and a determination made with or without a formal court hearing, as to whether the death was caused by an unlawful act or omission.” Code of Criminal Procedure Art. 49.01 (2).