TODAY | April 22, 2012
>>> four years after his run for president ended in scandal, former democratic presidential candidate john edwards goes on trial tomorrow. he's charged with misusing campaign funds in an attempt to hide his extramarital affair . nbc's senior investigative correspondent lisa myers explained why the saga of edwards ' downfall is not over yet.
>> reporter: this man, once a promising candidate for president, once regarded as a brilliant trial lawyer , now finds himself facing a judge and a jury. prosecutors have charged john edwards with receiving almost $1 million in illegal campaign contributions , money used to hide his mistress, rielle hunter, from the press while he was running for president. kieron shanahan is a former federal prosecutor . did that smell like something was going on?
>> it does, and i think the one problem for the defense is, the average person, when you talk about $1 million, is real money and a lot of it.
>> reporter: edwards says the evidence will prove he did not know about the money.
>> i finally get my day in court and people get to hear my side of this and what actually happened.
>> reporter: edwards says the money was not a contribution but a gift from two wealthy friends who provided funds to protect his wife, elizabeth, from the humiliation of his affair. law school professor katherine dunham says there has never been a case like this.
>> this particular section of the federal election law and the definition of what a contribution is has never been challenged in this way.
>> reporter: there's no question, john edwards has credibility issues. he lied about his affair. to counter that, the defense will attack the truthfulness of the government's star witness. former aide andrew young admits he has lied, falsely claiming paternity of the child edwards had with hunter. while young is expected to testify edwards directed the money, edwards says in a court document that young actually pocketed a lot of the money. young was not available for comment.
>> i think a central theme in this case is going to be one admitted liar against another admitted liar.
>> reporter: the pivotal question, which man should the jury believe? for "today," lisa myers , nbc news, washington.