Why backpeddle on the Federalist Society?

Ever since Roberts has been nominated to the High Court, he and the Bush administration have been backpeddling on his membership regarding the Federalist Society. Why shy away from it. In case the Republicans haven't realized, they have the majority. Republicans are always so embarrased to be conservative. This lack of fortitude casts doubt over whether Roberts will be able to make tough decisions.

He said in a Senate questionnaire that he had "no recollection" of being a member of the Federalist Society. But he was on one of the group's panels in 1993, was listed in a 1997 brochure as a member of the steering committee of the society's Washington chapter, and gave a luncheon speech to the legal group in 2003. ...

The White House says Roberts has been candid in his written responses to Senate
questions. "John Roberts never joined" the Federalist Society, Bush spokesman Steve Schmidt said Wednesday. "He has spoken on panels sponsored by the Federalist Society, he was on a steering committee, but not a member." AP