In April, Brian I. Ford walked into a Fairfax City pawn shop with a Civil War-era musket and walked out with a $35 loan. Several weeks later, when he returned to make a payment on the loan, he was arrested for being a felon in possession of a firearm, after police checked and found he had old convictions for burglary and robbery.

When Ford went to trial last week in Fairfax County, a jury quickly convicted him and recommended a fine of $1,250 but no jail time, though it could have recommended up to five years in prison.

If Ford's case were to come up now, the jury would have no choice but to send him to prison. Under a law that took effect July 1, felons in possession of firearms in Virginia receive a mandatory sentence of five years, minimum, in prison without parole.

New signs and billboards are springing up along highways around the state warning motorists of the new law known as "Virginia Exile."

As the warnings posted on the Capital Beltway and bridges leading from the District say: "Illegal gun? Five years in Virginia prisons."

The initiative championed by Gov. James S. Gilmore III (R) passed both houses of the General Assembly unanimously and aims to reduce violent crime by imposing harsher penalties on gun violations. But it also throws Virginia deeper into the debate over mandatory minimum sentencing, denounced by many judges and defense attorneys as a concept that takes away a court's discretion to review each case individually and corrals all defendants into a single, inflexible pen regardless of their circumstances.

Gilmore pushed the law after claiming that a similar program in Richmond, "Project Exile," had reduced the number of homicides there by 40 percent in just two years. Because federal laws provided minimum five-year sentences for many gun violations, federal prosecutors agreed under "Project Exile" to handle gun cases normally filed in state court, where a five-year penalty was rarely imposed. Other cities, including Denver, Philadelphia, San Francisco and Kansas City have since adopted the Richmond model of federal-state cooperation on gun crimes.

Now, Virginia's penalties are the equal of the federal system's, and local prosecutors can obtain five-year minimum sentences in certain cases: where a convicted felon is in possession of a gun; where a gun is used or is brandished near a school, or when a defendant in possession of illegal drugs also carries a gun.

"Virginia Exile gets straight to the point," Gilmore said in a speech shortly after the law went on the books. "Drugs--felons--schools, and a gun associated with any one of them gets you five years in a Virginia prison. . . . No suspended sentence, no probation, and very likely, no bail."

The law also instructs judges to presume, unless convinced otherwise, that anyone charged with a gun crime or other violent offense can't be safely released on bond. And the Virginia Exile program provides almost $1 million in grants to local prosecutors for training and processing the new gun cases.

Robert Humphries, the commonwealth's attorney in Virginia Beach and an adviser to Gilmore on Virginia Exile, acknowledged that "there's a point to be made that 'one size does not fit all' " when it comes to sentencing criminals. But legislators made the policy decision, and in this instance "the legislature has tied the hands of judges because the public and the legislators don't like the things judges are doing."

Some judges and defense attorneys are dismayed by the proliferation of mandatory sentencing. Earlier this year, U.S. District Judge Richard Williams of Richmond complained in a letter to U.S. Chief Justice William H. Rehnquist that Project Exile had turned federal court "into a minor grade state court."

And Rehnquist has been a longtime critic of mandatory minimums, saying they "impose unduly harsh punishment for first-time offenders and have led to an inordinate increase in the prison population."

Except for the Virginia Exile law, the state has sentencing guidelines that are not mandatory and judges may deviate from them. In jury trials, juries recommend sentences that judges may reduce but not increase. But mandatory minimums trump the guidelines and place strict requirements on what juries or judges can do in the sentencing phase.

"Who don't we trust?" asked Kyle O'Dowd, general counsel for Families Against Mandatory Minimums, a Washington-based lobbying group. "The judges? The people who elected the legislators? Regardless of a person's background or pleadings, they're going to get the same sentence everyone else gets, and at the state level it's very expensive because of the increased incarceration."

Richard Kern, director of the Virginia Sentencing Commission, said the result of mandatory minimums in the federal system was more plea bargaining to avoid stiff sentences. Richard C. Goemann, the public defender for Fairfax County, argued that "puts much more power in the prosecutor's hands," by giving the government the threat of five-year terms both in filing charges and in plea bargaining, "and takes it out of the judges' hands."

But S. Randolph Sengel, the commonwealth's attorney for Alexandria, responded that "the original discretion lies with the [defense] clients, in terms of whether or not they choose to use a firearm. That's the whole point, to send a message that this type of conduct is not high on the list of things we like to tolerate."