Week four of the John Edwards trial began Monday with the defense calling its first witness and fighting to include testimony from someone they say is vital to their case.

Judge Catherine Eagles has yet to rule whether former Federal Election Commissioners will be allowed to testify.

Also on the witness list are Edwards' daughter Cate and his mistress Rielle Hunter, though there is concern she could shift attention back to the salacious side of the case.

Another risk apparently being considered by the defense: Calling Edwards to the stand.

"There's always the possibility that John Edwards might testify, but lawyers make poor witnesses, especially lawyers who are used to winning all the time and especially a lawyer where we saw videotape of him on 'NightLine' lying. That is what the jury saw," notes Elon University law professor Steve Freidland.

Edwards' defense team has said they expect their case to last two to three weeks.