Leo Varadkar (Dublin West, Fine Gael) | Oireachtas source

-----and the other being a mechanism which allowed stateless corporations to avoid paying tax, but it is a constant game of cat and mouse. There are very smart tax lawyers who go through legislation looking for loopholes to exploit. It is never going to be the case that there will be no loopholes and we must keep on closing them. The Deputy knows full well that it is not possible to change the law retrospectively. That applies to citizens, as well as to companies. We could not pass a law here today to change the income tax rates four years ago and expect people to pay up. Laws have to be prospective, not retrospective.

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