“When you have that attitude,” she said, “you penalize people who have the nerve to go to trial.”

Prosecutors say they are giving defendants options and are merely charging them based on what is allowed under the law for those who turn down pleas.

While legal experts say the effect is clear in persuading more defendants to forgo trials, the trial penalty is hard to quantify without examining individual cases and negotiations between prosecutors and defense lawyers.

That is because threats of harsher charges against defendants who reject plea deals often are the most influential factor in the outcome of a case, but this interplay is never reflected in official data.

“How many times is a mandatory sentence used as a chip in order to coerce a plea? They don’t keep records,” said Senior Judge John L. Kane Jr. of United States District Court in Denver, who believes that prosecutors have grown more powerful than judges. But it is very common, he added. “That’s what the public doesn’t see, and where the statistics become meaningless.”

But one result is obvious, he said: “We hardly have trials anymore.”

In 1977, the year Judge Kane was appointed to the bench, the ratio of guilty pleas to criminal trial verdicts in federal district courts was a little more than four to one; by last year, it was almost 32 to one.

Here in Florida, which has greatly toughened sentencing since the 1990s, felony defendants who opt for trial now routinely face the prospect of higher charges that mean prison terms 2, 5, or even 20 times as long as if they had pleaded guilty. In many cases, the process is reversed, and stiffer charges are dismissed in return for a plea.

Before new sentencing laws, the gap was narrower, and trials less risky, veteran lawyers here say. The first thing Denis deVlaming, a prominent Florida criminal defense lawyer, does with a new client is pull out a calculator to tally all the additional punishments the prosecutor can add to figure the likely sentence if the client is convicted at trial.