Who should be in charge of enforcing these policies?

Given the prominence of chronic traumatic encephalopathy (CTE) in the news, and its relation to violence, self-harm, and neurodegeneration, state your opinion about current “return-to-play” strategies in: (a) youth sports; (b) high school sports; (c) college sports; and (d) professional sports. Who should be in charge of enforcing these policies?