New offshore tax laws not powerful enough

Doubts have been raised about whether planned new laws will be powerful enough to rake in billions of offshore tax dollars from multi-national companies.

Treasurer Joe Hockey has promised to stop companies using complex schemes to escape paying tax, but University of Sydney academic Anthony Ting says a close look at the draft legislation suggests it is far from comprehensive.

"It is a step in the right direction - but possibly not a big enough step," he wrote on The Conversation website, adding only two of the five multinational companies nominated by the treasurer - Google and Microsoft - were likely to be covered.