Why did Labour back axing of planning probe?

I found it ironic to hear Labour Minister Joan Burton over the weekend saying that the basic rules of planning were contravened due to the corruption which permeated the various levels of the process.

Why, then, did Labour support Minister Hogan’s blocking of the independent review into planning irregularities in Dublin and Cork City councils and Meath, Galway, Cork and Carlow county councils less than 12 months ago?

This review had been set up by the former Minister of the Environment John Gormley and was about to begin investigating. Surely the Mahon Tribunal should be the start of cleaning up planning and politics?