The introduction of an adult rating for games in Australia--which is slated to be introduced sometime in 2012--will come too late for EA's new take on the Syndicate franchise. The game has been refused classification by the Australian Classification Board, meaning it's illegal to sell or market it in the country.
A listing on the Classification Board website has confirmed the banning, but EA has not yet officially commented on the situation. GameSpot AU has also reached out to the board to obtain more detail on the banning.
While exact details on why the game was banned are not known, Syndicate did feature scenes of tense violence, including an ability to take over enemy minds and force them to commit suicide.
GameSpot AU will have more details on the Syndicate ban as more information comes to light.
UPDATE: The Classification Board has now released its decision report into Syndicate, which states that the game was indeed refused classification because of its high impact violence.
In its report, the Board cited several examples of high impact violence, including the fact that "combatants can take locational damage an can be explicitly dismembered, decapitated, or bisected by the force of the gunfire. The depictions are accompanied by copious bloodspray and injuries are shown realistically and with detail. Flesh and bone are often exposed while arterial sprays of blood continue to spurt from wounds at regular intervals."
"The game also allows a player to repeatedly damage enemy combatants' corpses. For example, it is possible for a player to decapitate a corpse with a headshot before individually blowing off each of its limbs."