http://www.abc.net.au/news/2012-04-20/illegal-downloading-more-like-trespass-than-theft/3963688
He says illegal downloading is more similar to the crime of trespass than it is to theft.
"To say that there was a trespass is traditionally understood to mean that there was a temporary use of someone's property without permission," he said.
"If someone trespasses on your property it means that they've come uninvited but they haven't deprived you of use. They haven't deprived you of the basic possession of the property.
"But to say that someone's stolen something is to say something much more serious. It's probably the single most substantial form of property crime that we have.
"And that's exactly what the music and movie industries in the United States would like to happen. They want people to think that illegal downloading is just as bad and should be punished just as severely."
Professor Green says that stance needs to change.
"I think we really need to re-think that because people seem to be resisting it," he said.
"And unless the criminal law ultimately is consistent with people's norms and the way people think about it then it has the effect of sort of undermining the effectiveness and the legitimacy of the law if people really don't take the law seriously."