VICTORIA, Texas (AP) — The relatives of a 76-year-old man want a South Texas police officer prosecuted for a traffic-stop scuffle in which a stun gun was used on him, an attorney for the family said.

Rachel Messer told reporters after a police news conference on the case that Pete Vasquez’s family hopes for “a full criminal prosecution” of Victoria police officer Nathanial Robinson.

“We do believe that his actions were unlawful,” Messer said of Robinson, “and I think a lot of people believe that.”

At the Wednesday news conference, Victoria Police Chief J.J. Craig said the internal investigation into the Dec. 11 scuffle continues. Vasquez, of Victoria, was stopped for an expired vehicle inspection sticker.

Craig said Robinson, 23, has not been the subject of any substantiated misconduct accusations in his nearly two years on the police force. The chief said he expects the internal investigation to be completed by the weekend but that it could remain open until after Christmas.

“I want to emphasize to ask for patience while we conduct a full, fair, thorough investigation,” he said.

Meanwhile, Robinson remains on paid administrative leave.

Police dashboard-camera video captured the struggle between Robinson and Vasquez. Robinson tackled Vasquez to the ground and used his stun gun on him twice.

Texas Rangers are conducting a separate investigation.