As one officer played Gray’s role, lying face down on the floor, the other bent his crossed legs back toward his head. Watching closely were members of the police task force investigating Gray’s death, and Dr. David L. Higgins, a Maryland orthopedic surgeon who has worked with the U.S. Olympic team.

Higgins had already reviewed cellphone video showing the 25-year-old’s arrest in West Baltimore, including scenes with him yelling in pain or protest as officers dragged him to a transport van. Now, Higgins was asked what injuries a person could suffer in such a leg hold.

“From that maneuver, even if you slammed him or dropped him like a wrestling move, you still won’t have a neurological injury,” said Higgins, continuing to explain in more detail.

“OK,” said Maj. Stanley Brandford, the Homicide Unit commander who led the task force. He marked another task complete. Another question about Gray was answered.