A social diversity advocacy group said Wednesday that it collected 40,000 signatures on a petition calling for the Texas district attorney in the county where Sandra Bland was arrested to prosecute the involved officer. Bland, who officials have said committed suicide after three days in the Waller County jail where she was booked, fueled an ongoing debate about police conduct and accountability in the U.S.

People who signed the ColorOfChange.org petition say they want Elton Mathis, the Waller County district attorney, to prosecute Texas State Trooper Brian Encinia for wrongful arrest and alleged assault of Bland. Organizers at ColorOfChange said a lack of prosecution gives an impression that the agency simply wags its finger at officers who violate law enforcement regulations.

“There is no excuse as to why District Attorney Mathis hasn’t charged Officer Encinia already,” Arisha Hatch, the campaigns director at ColorOfChange, said in a statement Wednesday. “[DA Mathis’] failure to do so is only further proof that his investigation is a sham. As we have seen in Cincinnati and Baltimore, when prosecutors do their job, they investigate and prosecute abusive and discriminatory police within a matter of days.”

Encinia has not been fired or indicted on charges for his July 10 arrest of Bland, whom he pulled over for failing to signal before a lane change. Instead, the officer returned to regular patrol after a brief reassignment to desk duty, Hatch said.

Mathis formed an independent investigative panel last month to review the arrest and death of Bland. The panel includes at least one former colleague and a current associate of Mathis, civil rights groups have complained.

Members of Bland’s family and activists around the county questioned Encinia’s justification for arresting her on charges that she assaulted him, especially when his action escalated the encounter. Footage from a police dashboard camera video showed that Encinia drew his Taser and threatened to use it on Bland. The dashboard camera did not capture the arrest, but video filmed by a pedestrian did show Encinia on top of Bland during the arrest.

“Let's be clear: Waller County officials cannot handle the investigation of Sandra Bland, and we need Attorney General Loretta Lynch and the Department of Justice to act now and provide authentic independent oversight into discriminatory practices that led to Sandra's death,” Hatch added in the statement.