Shouldering the Blame

The shoulder charge by the non ball carrier is illegal in Rugby Union, but perfectly legal in League, as long as executed correctly and not dangerously. In particular the shoulder cannot directly impact with the opponent's head. Sometimes this is a matter of timing rather than intent. Nonetheless direct head contact from the shoulder places the 'tackler' at risk of a red card for a dangerous play. The referee is required to make a judgement call. This week 2 similar incidents in the Super League resulted in differing outcomes on the field of play, but bans for both offending players subsequently. Hull FC's forward Sam Moa was red carded for a shoulder charge which knocked London Broncos Julien Rinaldi unconscious. The point of contact was directly with Rinaldi's head. Conversely Tommy Lee's high hit on Lee Briers during the Huddersfield v Warrington encounter escaped punishment during the game, but was reported by the Rugby League Review Panel.
The distinction between the 2 codes appears from the outside to be a question of culture with Rugby League embracing a more macho attitude and celebrating the 'big hits'. Phil clarke put it thus: I think that every player in Super League has to undergo an initiation test. Their journey into manhood or acceptance by their peers usually involves some degree of pain and bravery'. New Zealand star Sonny Bill Williams was famous for bone crushing shoulder charges on ball carriers, but his hits were targetted at the chest area and did not ordinarily result in head contacts and concussive injury. http://www.sportsillustrated.co.za/rugby/why-sb-got-off-for-shoulder-charge/ Unfortunately when he transferred codes to Union in controversial circumstances in mid season 2008 and joined Toulon in France, he was dismissed for a similar shoulder challenge in his very first game. Interestingly the Toulon owner, Mourad Boudjellal, suggested that perhaps Rugby League was a 'tougher game' and that Williams would take time to adapt. I find it hard to believe that Union afficionados would accept that League is a tougher game.
Interestingly the shoulder charge is also outlawed in Australian Rules and Gaelic Football, but allowed in American Football (Gridiron).
There are endless debates about dangerous techniques in all forms of football. Alhtough the shoulder charge is legal In American Football, the 'horse collar tackle' was outlawed in the 2005 off season. The tackle involves the grabbing of the back inside of a player's shoulder pads or by the back of the neck of the jersey (scragging). The technique became known as the 'Roy Williams Rule'. Williams had been involved in 4 major incidents using this method of tackle which resulted in serious injury during the 2004 season. http://www.dallasnews.com/sharedcontent/dws/spe/2005/horse_collar_tackle/
Ultimately only significant repeated incidents of serious injury appear to prompt rule changes against the marked reluctance of most in whichever form of football to water down the combative physical aspects of their sport. The definition of a 'dangerous play' is highly subjective and counter balanced by a desire to preserve the spectacle. Sporting stardom is frequently glorious but precarious.