1.   Lay has refused to respond to questions about the collapse.

2.   Lay has refused to testify before two other congressional committees.

3.   Lay has refused to testify before Congress, invoking his Fifth Amendment constitutional right against self-incrimination at a Senate hearing on Tuesday.

4.   Lay has refused to testify before Congress, invoking his Fifth Amendment privilege against self-incrimination.

5.   Lay refused to appear voluntarily before the Senate committee on Monday to explain how top Enron executives walked away from the failed company with millions of dollars.