We have Rules and Laws in our lives and our government to maintain stability and order. They exist for the stability of the way of life in which we live. To be issued a Subpoena is to be, by law, ordered to appear and give testimony under oath, 'To-Tell-The-Truth-The-Whole-Truth-And-Nothing-But-The-Truth!' If the oath is violated and it is discovered that the statement that was given under oath to be a lie, then the person under oath is charged with perjury, which carries with it a penalty of prison time.
So why would someone who is/was a member of the Bush Administration feel that he/she does not have to be sworn in prior to their testimony. Could it be that the person knows that their statement would perjure himself/herself. In other words, that person wants to 'LIE' and not be charged with perjury. Remember that refusing to co-operate with an order of subpoena is breaking the law. That is why Republican Linda Sanchez, who is the Chairman of the House Subcommittee, ruled that Republican Karl Rove was breaking the law to co-operate with the Congressional Subpoena by refusing to testify.
Other Republicans are calling it a political ploy of the Democrats in insisting that Karl Rove give an oath to say the truth and nothing but the truth in his testimony. Yet Republican Linda Sanchez recognizes the law, and unlike her fellow Republicans, is under the legal oath of following the letter of the law just as the Democrats on the House Subcommittee are under the legal oath to do.
I wonder if any of us could so easily 'REFUSE' to give the sworn oath, thus allowing us to lie in our testimony, if we at any time are ordered by a subpoena to testify in court. I guess we all know the answer to that one.