From our Expert Voices conversation on pro football.

Many fans deny moral responsibility for the dangers of football by claiming that players freely choose them. But do they? The newest CTE studies show that brain trauma from football is less a risk than a likely outcome. We need to consider what truly informed consent to this outcome requires, and whether it's possible.

Ethicists generally agree that you can't truly consent to something if you are ignorant of its risks and consequences. Players may know that football is risky, but few have known how dangerous until too late — in part because of the NFL's documented efforts to discredit CTE research. It's even worse when we consider that most elite players begin playing football when they are children, incapable of fully understanding the risk.

Meanwhile, "toughing it out" and playing through pain can earn big rewards in the form of fan attention — and, importantly, money. Fans help provide a significant incentive to play football, even in the absence of a full grasp of its consequences.

Bottom line: We can't avoid our own responsibility for the dangers of football. Pretending we can make it safe is not enough; we need a public conversation about how to ensure meaningful consent to it, and to discourage kids from playing until they can plausibly understand what it means.

Read the other voices in the conversation:

• Doug Patteson, CFO of Turbocam and a former CIA operative: You can't engineer out all risk
• Andrew Zimbalist, professor at Smith College and author of Rio 2016: Players should get battle pay
• Michael Rosenthal, editor-in-chief, Ring magazine: The athlete is responsible