1. Just because someone has offshore accounts does not mean they are avoiding taxes.
That being said, the money that was transferred to these accounts should be looked at to verify that the appropriate taxes were paid prior to the transfer. If it hasn't been, nail their asses to the wall.
Hopefully some of the 550 people, family dynasties and companies can be investigated with relation to their political ties, plumb appointments, lobbying efforts, tax breaks and financial empires. I doubt that the CBC has the stomach or resources to do that though.