The man accused of shooting Congresswoman Gabrielle Giffords and 18 others in Tucson last year wants to plead guilty, according to sources familiar with the case.

The federal judge handling the case had scheduled a status hearing in Tucson for this coming Tuesday to get an update from prison doctors treating Jared Loughner, who's been undergoing mental health treatment in a Bureau of Prisons hospital since shortly after the shooting.

Loughner now wants to plead guilty at that hearing, and the doctors treating him are prepared to testify that he's mentally competent to offer the plea, these sources say.

Acceptance of a plea from Loughner will not be automatic. Under federal court rules, the judge must be satisfied that a guilty plea is "knowing and voluntary." That will require the judge to ask Loughner a series of questions in open court to make certain that he has the capacity to understand what a guilty plea means, including the fact that he gives up all his appeal rights.