March 26 (Reuters) - The Supreme Court's rulings last week bolstering defendants' rights to effective counsel during the plea bargaining process drew praise from criminal defense attorneys, who said the decisions would help improve pre-trial rights for their clients.

But before Lafler v. Cooper and Missouri v. Frey will begin to impact the way defense lawyers handle plea negotiations, state and federal courts will have to resolve lawsuits by defendants seeking to overturn their convictions based on inadequate legal representation.

Once those decisions begin trickling down and creating a new body of law, lawyers will likely shift the way they deal with plea offers.

"Today a public defender can meet the client and say 'The government has offered a deal, if you are guilty you can go home tonight and if you are innocent you can wait in jail some more. You have 15 seconds to decide,'" said Albert Alschuler, a professor emeritus at the University of Chicago Law School and an expert on plea bargaining.

"That's probably not going to cut it anymore. The lawyer is going to have to know something about the case."

In Lafler v. Cooper, a Michigan case, Anthony Cooper took his lawyer's advice and passed up a plea deal that would have sent him to prison for four to seven years for shooting a woman seven times. Instead, he went to trial and was convicted on all counts and sentenced to serve at least 15 years in prison. The lawyer had told Cooper he would not be convicted of assault with intent to murder because he shot the woman below the waist.

In that lawsuit, the majority held that when a lawyer's bad advice caused the defendant to reject the plea bargain and then stand trial, the defendant could now seek to have the conviction overturned.

In Missouri v. Frye, a case where the defense attorney did not communicate prosecutors' plea offers to his client, Galin Frye, the majority said that defense counsel as a general rule has a duty to inform his client of the deals.

Lawyers concede that in very rare cases defense counsel, in order to make the most money in the least amount of time, might urge a client to plead guilty rather than go trial. But the behavior of the defense attorneys in the Supreme Court cases was almost unheard of. The decisions, lawyers say, basically mandate defense lawyers do the job they ought to be doing anyway.

Rather than face a jury or judge, almost all defendants opt to plead guilty, often in the hope of obtaining a lesser sentence. Guilty pleas account for 97 percent of federal convictions and 94 percent of state convictions, noted justice Anthony Kennedy, who wrote the majority opinions in both cases.

"The Supreme Court is finally catching on to just what percentage of criminal justice is dispensed through plea bargaining," said American University law Professor Stephen Vladeck. "The Court may be late to the party, but it is arriving in style."

The rules governing plea negotiations differ from state to state. In some states, for example, prosecutors are not required to put a plea offer down on paper. State and federal courts are also under pressure to favor a quick resolution to cases in order to avoid the time and costs associated with trials.

But Wednesday's Supreme Court opinions will force judges to slow the plea process down at least enough to satisfy themselves that defendants received proper legal advice before pleading guilty.

At a guilty plea proceeding in Manhattan Federal Court on Monday, judge Lewis Kaplan asked a defense attorney if he had given his best advice to his client during plea negotiations.

"In light of the Supreme Court's decisions last week, I suppose I should ask you if... any other plea offers have been communicated to you that you have not shared with your client?" Kaplan asked attorney Barry Berke. "Have you given him (your client) your best judgment?"

Kaplan later accepted the guilty plea.

In state courts, the opinions could have a more wide-ranging impact and may eventually change local plea rules.

Zeke Perlo, of the Los Angeles County Bar Association where he helps indigent defendants get legal representation, said he hoped the rulings would help "kill off" a so-called "Early Disposition" program, which aims to ease clogging in the courts by offering quick deals to defendants accused of minor crimes.

Under the local program, defense lawyers are given limited time and resources to research the alleged offense, which makes it difficult for lawyers to properly advise clients on whether they should accept a plea, said Perlo.

As a next step, some defense lawyers suggested that the court should focus on increasing oversight of plea negotiations, where they say the government has too much power and far more resources.

"Competent advice of counsel in the plea bargaining process is essential, but let's not scapegoat defense lawyers in a process dominated by the government's immense investigative resources and charging power," said JaneAnne Murray, a criminal defense attorney who teaches at the University of Minnesota Law School.

"I hope that Frye and Lafler signal a deeper commitment on the part of the Supreme Court to scrutinize all parties' behavior and transparency in this pivotal but generally unregulated arena of the criminal justice system."

The Supreme Court cases are Lafler v. Cooper, No. 10-209, and Missouri v. Frye, No. 10-444.

(Reporting By Basil Katz)

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