Extraordinary new powers will allow police to arrest and fine people for "causing annoyance" to World Youth Day participants and permit partial strip searches at hundreds of Sydney sites, beginning today. 

The laws, which operate until the end of July, have the potential to make a crime of wearing a T-shirt with a message on it, undertaking a Chaser-style stunt, handing out condoms at protests, riding a skateboard or even playing music, critics say. 

Police and volunteers from the State Emergency Service and Rural Fire Service will be able to direct people to cease engaging in conduct that "causes annoyance or inconvenience to participants in a World Youth Day event". 

Thou Shalt Not Annoy On Youth Day