Do you not agree with this:
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Julian Lewis, the Tory chair of the defence committee, called for somebody to be sacked over the controversy.
Lewis told broadcasters: “This sort of event is not one you can play both ways. These tests are routine but infrequent in this country. Whenever they work, which is 99% of the time, film is released of them working, so whichever person decided they wanted to draw a veil over one that didn’t work should have been sacked. You have always got to assume that something like this will come out.”
He added: “This test went wrong in June when it was a question of David Cameron and his team being at No 10. They evidently decided to cover this matter up.
“The only way she could have disclosed this matter would have been to point the finger of accusation against her predecessor for covering it up. So a tricky situation, but on the whole I think if she did know – which she probably did – she should have spoken up.”
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i.e. It wasn't her decision to cover it up and once she was told she was left with choice of saying nothing or immediately accusing Cameron of covering it up.