By Cherri Gregg

PHILADELPHIA (CBS) – The United States Supreme Court ruled for the first time that criminal defendants have a constitutional right to effective counsel during the plea bargaining stage of a case and they could be entitled to a new trial if their lawyer wasn’t up to par.

The 5-4 decision focused on two cases: one where a lawyer fails to inform his client of the DA’s offer and another where the attorney advised his client to reject a plea based on law that was, well, just wrong.

“Clients have a right to effective counsel,” says Charles Cunningham, who has defended criminal cases for the Defender Association of Philadelphia for more than two decades. He says the vast majority of the cases he’s seen, have ended in a plea.

“The Commonwealth wants to dispose of the case. The courts want to dispose of the case. If you as a defense attorney and you as the defendant want to dispose of the case, you may be willing to accept the offer.”

That’s why he says rules governing attorney conduct already require that lawyers inform clients of all plea offers and advise clients on the law and the facts of the case. But Cunningham says a huge problem is that it’s difficult to unring the bell if a plea is rejected and a defendant is convicted, so some may use the Supreme Court decision to get a new trial.

“Then it will boil down to a question of credibility between the client and the attorney.”