TULSA, Oklahoma - A grand jury is scheduled to convene Monday to begin an investigation into the Tulsa County Sheriff's Office. Fifteen people out of 100 potential jurors will be selected to be a part of that grand jury.

During the process, jurors can ask for any piece of evidence and subpoena people to testify. The process could take a number of months.

The Sheriff's Office has been under scrutiny after the shooting death of Eric Harris, a Tulsa man who died during an undercover gun sting. Reserve Deputy Bob Bates said he accidentally pulled his gun instead of his Taser while trying to subdue Harris.

Bates has been charged with second-degree manslaughter.

Okmulgee County District Attorney Rob Barris will come to Tulsa to assist the jurors in the investigation. Steve Kunzweiler, the Tulsa County DA, requested Barris be appointed as the Tulsa office has historically provided representation to TCSO. Kunzweiler wanted to avoid any appearance of a conflict of interest.

Last week, Tulsa County Sheriff Stanley Glanz's legal team lost an effort to stop the investigation into his office. The Oklahoma Supreme Court denied the sheriff's motion to stop the process. 

A group called "We The People" collected signatures on a petition calling for the investigation.The sheriff's team argued the signatures were collected improperly, but Tulsa Judge Rebecca Nightingale ruled the process should go forward - and the State Supreme Court agreed.