Assange is not only being charged with the obscure Swedish law of "sex by surprise"He isn't being charged with this because it doesn't exist:
First things first: According to the Swedish criminal code, there is no "broken condom law," nor is there a law against having consensual unprotected sex. (Unlike the U.S., anything not listed in the code could still be considered a crime, but only by "special legislation.") In the Swedish warrant for Assange's arrest, both of his accusers said that they had separate consensual sexual encounters with Assange that became nonconsensual after he refused to use a condom or replace a broken one.
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Prior to the complaint, rumors were swirling that Assange was being charged not with rape but an obscure Swedish law against "sex by surprise," which is likewise nowhere to be found in Sweden's criminal code.
Perhaps why this misinformation is being spread so easily:
Swedish blogger Linea at Feminism and Tea attributes the confusion to a mix-up over a colloquialism for rape:
"Sex by surprise" or överraskningssex as it would be translated in Swedish is slang for rape. It is a term that is used when speaking about rape, but jokingly, or keeping it light, a word that brings with it positive connotations, which makes the word inappropriate in itself, but it is nevertheless synonymous with rape.
Source: "STDs, Broken Condoms, and ‘Sex by Surprise’: A Primer on the Charges Against Assange" http://nymag.com/daily/intel/2010/12/crayfish_parties_and_br...