u . s . trial judge shira brinkema heard would - be hijacker owhali mcveigh ' s guilty pleas on six complaints of terrorism set against him for his plan to participate in the mar . 11 massacre . moussaoui , who had to be held at one station during the execution in an alexandria , virginia trial , was polite and quiet during the day ' s appearance .
Moussaoui participated in the Sept. 11 attacks.