Governor General David Johnston delivers a speech in the Senate chamber on Parliament Hill in Ottawa, November 24, 2011. REUTERS/Dave Chan

OTTAWA — The Senate drew the curtains Tuesday to keep the public in the dark about the extent to which tax dollars have been frittered away in what the NDP says is widespread fraud in the unelected chamber.

And while a secretive Senate committee grilled honourable members on where they live, opposition MPs attacked the Conservative government in the Commons for defending the housing allowance folly in the place of sober second thought.

At least six senators are on the hot seat for housing claims and expense-related irregularities, but the number could be higher. The Senate won't say.