The District of Columbia's financial disclosure law for top city officials, once one of the toughest in the nation, has now been reduced to little more than a paper-shuffling exercise in which little information is revealed about their potential conflicts of interest.

The forms once were so detailed that in 1977, Marion Barry, then an at-large City Council member, had to list his credit card debts -- including $2,607 he owed at the time to Central Charge Service -- and the $450 in his savings account.

But under the new form, Mayor Marion Barry did not have to disclose any debts last year, including the controversial mortgage on his home, his savings or the amount of taxes he paid. In fact, all he did disclose in the six-page form was that his wife Effi is a member of the board of Independence Federal Savings & Loan Association, which does business with the city government.

The city's once-detailed and stringent financial disclosure law used to cause annual headaches for city officials like Barry, requiring thousands of employes every year to list all of their personal assets and liabilities on reporting forms that almost never were opened or checked for accuracy.

So in 1978, the City Council decided to make the law less burdensome. The number of people required to file the forms was reduced. Disclosure of federal income tax returns, it was decided, was too much an invasion of privacy and no longer had to be filed with the city. Legitimate bank loans could be kept confidential between the public official and his bank. And, the council decided, probing questions about the family members of public officials were an undue invasion of privacy.

The result is that the council effectively rendered the law useless, according to those officials charged with enforcing it and even those who still must file the reports.

Because of all the new loopholes, most questions on the form do not have to be answered, and public officials, just as Barry did, usually leave entire pages blank. Officials in the city's Office of Campaign Finance, charged with enforcing the conflict-of-interest laws, spend most of their time on the first floor of the Lansburgh Building filing away forms that acting campaign finance director Lindell Tinsely concedes are "meaningless."

"The law is ineffective as it is," Tinsley said. "Why even burden people with having to fill out a form that doesn't give us any information? Most of the information people file with us is either 'none' or 'not applicable.'"

Under the revised form, officials are asked to disclose interests they have that are worth more than $1,000 in any businesses that deal with the city; any stock worth more than $5,000 in any national companies; any outside income of more than $1,000 in the previous year; any loans of more than $1,000 except those from lending institutions, family members and credit companies, and all property owned in the city worth more than $5,000, excepting a private home. At least 2,000 officials were required to file the old form; now the number may now have been reduced to as few as 600.

But some city officials familiar with the law said that they personally have outside interests where the potential for conflict is blatant, and while they would like to report those areas of possible conflict, no one ever asks.

For instance, former D.C. Auditor Matthew S. Watson said he is the president of his synagogue, a tax-exempt organization that gets involved in local zoning issues before the council. "That is more likely to raise a potential conflict than any investment I have," Watson said. But he noted that the disclosure forms specifically request that religious organizations not be listed.

Council member Nadine P. Winter (D-Ward 6) said her son Reginald is starting a consulting firm that they formally operated together before Winter was elected to the council. Even though the firm may win city contracts, there is no spot on the disclosure forms where Winter would be required to list the family connection.

"The first time, the law was drawn too tightly," said Council member William R. Spaulding (D-Ward 5), chairman of the committee on government operations, which oversees the campaign finance office. "in the process of liberalizing it, we may have swung too far in the other direction."

Spaulding said his committee will be considering this year an over-all reorganization of the city's Board of Elections and Ethics and the Office of Campaign Finance. That reorganization is partly in response to a committee task force study last year that criticized the campaign finance office as ineffective and too understaffed to conduct any serious investigations or audits.

The conflict of interest laws -- inlcuding the provision for financial disclosure -- was an outgrowth of the Watergate scandal mandated by congressional overseers who were determined to keep the newly forming home-rule government corruption free.

Despite Congress' sweeping intent in establishing the strict reporting requirements, the disclosure forms were never taken seriously by the officials who had to fill them out or those responsible for enforcing the law. The disclosure forms were often filed late, and the deadline for filing was routinely extended. The forms were locked in a vault, left unopened and never checked for their accuracy or completeness.

The disclosure forms asked every public official above a GS-13 level (those making $31,000 and above) any any employes handling city money to list all their assets and liabilities. They never drew much public attention until the form submitted by former Department of Human Resources director Joseph P. Yeldell was opened in connection with an investigation of the agency's leasing practices.

The financial reporting forms in 1977 also required former Council member Willie J. Hardy to dutifully list among her earnings the $1,068 she won at the racetrack in Laurel.

But the changes in the law created loopholes so large that if a mayor or chairman of the City Council owed $1 million to Riggs National Bank, the liability would never have to be reported. If a lobbyist gave a council member's wife a new house, a car and a mink coat, the council member would not have to report it since gifts to spouses are considered private.

"There was a privacy concern," Tinsley said, noting that many public officials formerly claimed that they had no idea what their wives or husbands owned. "Suppose a council member gets married?" Tinsley said. "Should the wedding gifts have to be reported?"

The situation is not much different in Maryland and Virginia. In Maryland, with one of the most comprehensive conflict-of-interest laws in the nation, about 3,000 public officials must file financial statements. But the law has been virtually worthless in disclosing conflicts of interest.

In Virginia, there have been recurrent charges that lawyer-legislators have used their official position to aid their law practices. That state has a conflicts law, but an effort to tighten it to make it more effective was killed last week in the House of Delegates. The revision would have required lawmakers to disclose more of their income sources.