  Others have suggested that, in their current form, collision sports such as American football and combat sports such as boxing should be banned by the state. Nicholas Dixon (2001) has argued on autonomy-based grounds that boxing which involves blows to the head should be banned, but boxing that limits the permissible target area to the area between the waist and the head should be permitted. Others have defended the status quo on the grounds that any attempt to criminalise boxing will lead to the sport moving underground where more harm may result (Warburton, 1998).