The World Bank Group has developed another interesting ranking. It helps identifying specific risks due to differences in a countries legal framework.

"...Doing Business database provides indicators of the cost of doing business by identifying specific regulations that enhance or constrain business investment, productivity, and growth..."

It currently uses indicators such as credit markets, entry regulations, bankruptcy procedures, contract enforcement and labor regulation. In most of these categories common law based countries have an advantage in terms of speed and less red tape.