"would the same thing be against the law if it happened here" is a somewhat common benchmark in treaties and laws about respecting and acting on foreign law enforcement requests, presumably that's what's meant. (When it comes to extraditions it's often called the "dual criminality" requirement, and can involve quite a bit of transfer to make things comparable. E.g. since Assange is charged with conspiring with Manning to steal US military data, the UK extradition ruling was considering if it would have been a crime in the UK if he had conspired with a UK service member to steal UK data)