[bigjohn]

From the 2010 NFHS slide show
Illegal Helmet Contact (Point of Emphasis):

In response to an alarming number of head and neck injuries resulting in death or paralysis during the 1960s and early 1970s, all forms of initiating contact with the helmet were ruled illegal in 1976. At the same time, coaches emphasized the illegality and danger of such tackling techniques and taught their athletes proper, safer methods of tackling and blocking. While catastrophic cervical spine injuries are still a danger, rates rapidly declined in the late 1970s and have stayed relatively low since that time.

Concussions have come under increasing attention in football during the past several years, garnering attention from television, newspapers and the United States Congress. The NFHS has been at the forefront of national sports organizations in emphasizing the importance of concussion education, recognition and proper management for the past several years. In addition, High School RIO and the National High School Sports Related Injury Surveillance Study provides the NFHS SMAC with information about concussion rates and mechanisms. Among the most concerning concussion data from the 2009 football season were that concussions accounted for 19.3 percent of all injuries reported and 63.1 percent of all concussions resulted from helmet-to-helmet contact!

Currently, illegal helmet contact is defined under NFHS Rule 2-20-1 as an “act of initiating contact with the helmet against an opponent.” There are three specific types of illegal helmet contact:
1. Butt Blocking is an act by an offensive or defensive player who initiates contact against an opponent who is not a ball carrier with the front of his helmet.
2. Face Tackling is an act by a defensive player who initiates contact with a ball carrier with the front of his helmet.
3. Spearing is an act by an offensive or defensive player who initiates contact against any opponent with the top of his helmet.

Clearly, any initiation of contact with the helmet by a player is already deemed an illegal act. However, given the frequency of this type of contact, these illegal methods of initiating contact continue to either be taught or condoned in practices, and are infrequently penalized during games. In light of increasing concerns about the incidence and severity of concussions in football, including the risk of death and long-term disability, the NFHS SMAC and the NFHS Football Rules Committee call upon coaches to insist that players do not initiate contact with any portion of the helmet against an opponent. Furthermore, officials must recognize and penalize all illegal helmet contact. Only through continual repetition of proper technique in practice including the correction of illegal acts when they occur, AND the consistent penalizing of illegal helmet contact in games will athletes lower the risk of concussion for their opponents and themselves.