Virginia laws prohibiting Sunday shopping and dating back before the days of George Washington and Thomas Jefferson were declared unconstitutional yesterday by the state Supreme Court.

So-called blue laws, which last year were repealed in Maryland and have not been in effect in the District for almost 20 years, were ruled unfair because they had been amended so frequently that they favored some businesses and discriminated against others, the court said. {The court also relaxed a ban on books. Story, Page B8.}

The 6-to-1 decision was prompted by a 1985 lawsuit in which six retail merchants and two development companies -- among them the Hechinger Co., K mart and Circuit City stores -- argued that Virginia's colonial-era laws had become a tool of "economic warfare" and no longer preserved a "day of rest," as they intended.

Chief Justice Harry L. Carrico dissented but did not write an opinion in the decision, which reverses a 1985 ruling by a Virginia Beach Circuit Court.

Although Northern Virginia jurisdictions have not been bound by the laws since they exempted themselves through a series of referendums in the mid-1970s, about 50 percent of all employed people in Virginia live in areas with Sunday closing laws.

Hundreds of stores in Norfolk, Roanoke, Virginia Beach and Hampton Roads will be affected by the ruling, prosecutors said.

Yesterday's decision erases a law that survived from 1610 to 1960 with few changes. Recently, however, the laws ran up against significant social changes, among them an increasing number of women working full time and shopping on the weekends. For many, the advent of malls also transformed shopping into a recreational pastime. And Sunday itself is not the day of church and family dinners that it once was.

As a result of these changes, Virginia lawmakers amended the original laws numerous times, continually broadening the exemptions until currently more than 60 "industries and businesses" are permitted to open on Sunday and the statutes cover about only 20 percent of the work force, according to Justice Charles S. Russell, who wrote the majority opinion.

The cumulative affect of the amendments, Russell wrote, "reduced the ambit of the law to a very few businesses" and is thus, unconstitutional under the state's prohibition against unfair "special laws."

Virginia's Sunday closing laws were originally intended to preserve the first day of the week for church-going and family outings. Then during the Revolutionary War their purpose grew more secular, becoming a means of providing a common day of rest "to prevent the physical and moral debasement which comes from uninterrupted labor," according to the 21-page opinion.

Until 1974, when the General Assembly began exempting a variety of retail stores and the operations of the agriculture, mining and manufacturing industries, most stores were closed throughout the state.

"It is the end of an era," said I. Michael Greenberger, the merchants' attorney. "As late as the 1960s, stores were generally closed except drug stores selling prescriptions. Now {for many stores} Sunday has become the most important day of the week . . . . People are not resting on Sundays anymore."

Sunday has, in fact, become the most productive business day for Washington area stores, according to Garry R. Curtis, manager of the retail division of the Greater Washington Board of Trade.

"Saturday is still the largest shopping day, but Sunday brings in the largest volume per hour," Curtis said.

But for many residents in Tidewater and southern parts of Virginia, Sunday shopping just isn't done.

Numerous times voters in Virginia Beach and other jurisdictions have opposed repealing the blue laws. As recently as 1982, 64 percent of the voters in Norfolk rejected a referendum proposing the laws' repeal.

The Virginia decision now means that there will be almost no area of the Old Dominion, Maryland or the District where a shopper can't buy everything from a pair of shoes to a pair of pliers any day of the week. The two remaining counties in Maryland that have blue laws, Wicomico and Allegany, are scheduled to hold referendums on them this fall.

"I'm relieved that there is finally a decision," said Virginia Beach Commonwealth's Attorney Paul A. Sciortino, the defendant in the suit brought in his jurisdiction. "I think with all the changes over the years, the law had become discriminatory."

"You could have a clothing and shoe store that couldn't open," Sciortino said, "but you could have a drugstore like Peoples that sold all the same things that could open."

Along with Hechinger Co., K mart and Circuit City stores, the other plaintiffs were Best Products Co., Rose's Stores, Zayre Corp. and the Benderson Development Co. S.L. Nusbaum & Co. Inc. was party to the original suit but recently withdrew.

John Hechinger Jr., president of the Hechinger Co., said the decision will affect eight stores in Virginia. "It's absolutely clear that the vast majority of the people like to shop on Sunday."

By most accounts, blue laws got their name from the paper they were written on and later came to refer to laws on morality and prohibiting certain Sunday activities.