When the District of Columbia Nurses' Association wanted to change the city's laws for licensing nurses, it went to City Council member Polly Shackleton, who introduced in almost identical form a bill drafted by the association as if it were her own.

City Council Chairman Arrington Dixon had some amendments tacked on a bill in May to provide a moratorium on condominium conversions in the District. The amendments were written by a lawyer for several realtors involved in condominium sales and delivered to Dixon by the president of the Washington Board of Realtors.

These are two of many possible examples of an increasingly common practice that recently came to light after Council Member Willie J. Hardy (D-Ward 7) offered legislation to slash unemployment compensation benefits for injured workers.

The 78-page bill and the 12-page proposed report were taken, mostly verbatim, from lobbying documents prepared by the Metropolitan Washington Board of Trade.

After five years of trying to get their way with the D.C. City Council through campaign contributions and buttonholing council members in the hallways of the District Building, special interest groups have found that the best way to get favorable legislation is to write it yourself.

The B.Y.O.B. syndrome - bring your own bill - has become a way of life in City Hall.

Lobbyists play a prominent role in shapeing legislation in Congress and nearly every state legislature, county board and city council in the nation.

However, in the D.C. City council, lobbyists, special interests and pressure group representatives have more opportunities to get directly involved in the legislative process at nearly every level than they do in the local and state governments of Maryland and Virginia.

In the District, lobbyists and special interest group representatives draft bills, amendments and committee reports, shop for and find sponsors and sit side-by-side with council members and their aides as active participants in some committee meetings at which bills are put in final form.

Key council members and their top aides say they have no desire to end the practice.

"They do it in Congress. They do it everywhere else," Shackleton (D-Ward 2) said with a smile. "In some cases. I think it's useful, especially when we have a piece of legislation with various conflicting views."

"Why do special interest submit legislation? Because they have special interests, to preserve and advance," said R. Robert Linowes, a lawyer active in politics and legislation in the District and in Montgomery County. "If you do it yourself, you can get it prepared sooner and you can get it done the way you want."

Dixon said, "if we had more staff, our dependence on outside assistance would be less."

"Outside assistance" takes many forms.

Shackleton's staff has received assistance in writing legislation from the American Bar Association, which is preparing model bills in the areas of mental health and retardation.

The staff of council member Wilhelmina J. Rolark (D-Ward 8) has a mail order catalogue of bills available from a legislative standards clearing house in Chicago. Rolark aides insist that they have seldom if ever used the catalogue.

However, Dixon has used at least one of those mail-order bills, one of his aides said - a "model" measure to change the city's probate law that was introduced but not passed last year.

Council members and staff aides interviewed said they don't feel the council members are betraying the trust of the city's electorate, which voted for them and which pays them $35,000 a year each to, among other things, write laws for the city.

The city pays $3,200 a year to belong to the organization that drafts the laws, the National Conference of Commissioners on Uniform State Laws. John McCabe, legislative director of the group, said that in recent years the District has been "relatively active" in its consideration of laws drafted by his organization.

Several laws that sparked considerable controversy in the city actually originated in large part with the conferecne, McCabe said. They include a measure proposed by Dixon in 1975 that would have allowed homosexuals to marry each other, and another will, proposed by David A. Clarke (D-Ward 1) that would have lessened the penalties for use of marijuana.

In the end, the members and staff said, issues are decided on their merits. They also said it is helpful to receive opinions of others as the legislation is being drafted.

"It's healthy," said Bruce French, the legislative counsel for the council. The more you have in terms of new ideas from whatever source, it gives the political process a better change to sift and decide and come up with the best laws for the District of Columbia."

"I'm sure there are those amendments that have slipped in, that if members had thought about it they wouldn't have done it," French said. "But these are rare."

Council member John Ray (D-at large) said, "It looks bad because it destroys the faith of people in government and in its integrity. But it would be impossible to prohibit it because you would outlaw a very valuable resource for the city."

"The problem is more one of appearance," Ray said. "If the Citywide Housing Coalition writes bills . . . no one gets upset. If the Board of Trade drafts a price of legislation for someone, everyone gets upset."

In the past, proponents of good government have argued that special interest groups that employ skilled lobbyists have had more influence in the shaping of laws than "public interest" groups with less money.

Rick Eisen, director of neighborhood improvement for the Metropolitan Washington Planning and Housing Association and a member of the executive committee of the Emergency Committee to Save Rental Housing, said tenant groups are just begining to lear the advantages other lobbies have enjoyed.

"If you've got somebody who can come in with some expertise and present an amendment and come up with a rational explanation for that, they (legislators) are more likely to do what you want," said Eisen, who has been actively involved as a lobbyist on behalf of tenant causes here.

Besides the case involving Hardy, another recent controversy was touched off by council chairman Dixon.

Dixon asked a council committee to consider legislation originally proposed by the Potomac Electric Power Co. that would tighten controls on the city's consumer advocate, who challenges rate increases proposed by Pepco and other utilities.

Dixon's wife works for Pepco, his general counsel is a former Pepco lobbyist and Dixon received nearly $5,000 in campaign contributions from Pepco, its officials and a law firm that lobbies for the utility. Dixon denied any conflict.

No estimate is available of how many of the 200 bills introduced into the City Council each year are written by special interests. Most council members insist they write most of their own legislation.

Many lobbyists shepherd their bills all the way through the legislative process.

Last week, for example, the council's consumer affairs committee completed the drafting of legislation that would required all family insurance sold in the city to include converage form newborn infants from the time of birth.

The legislation had been drafted originally by the city's association of pediatricians in consultation with the insurance industry and introduced by Shackleton in nearly identical form. Participating in the final session were representatives of the American Academy for Pediatrics, Blue Cross-Blue Shield, and the Health Insurance Association of America.

In the Montgomery and Prince George's County Council, the introduction of legislation that reproduces verbatim proposals by lobbyists is not as frequent as it is in the District, according to aides for those two councils.

In the Maryland General Assembly, lobbyists frequently find friendly sponsors to introudce their legislation verbatim. But the lobbyists seldom are allowed to take an open part in the formal sessions at which committees put the legislation in its final prepassage form, observers say.

Lobbyists drafting amendments in the back rooms is not uncommon, however.

In the Virginia Generl Assembly most bills are drafted by staff aides before being introduced. But lobbyists and special interest group representatives often work hand-in-hand with legislators and aides in drafting the final language of the measures before the full assembly votes on them, according to observers.

Legislators in the District say they are more dependent on outside help because of the small size of the city's legislation-writing staff.

The council has three attorneys whose primary job is drafting legislation. Three more attorneys give legal advice. The council also has about a dozen attorneys among the staff and committee aides. Three council members - Ray David A. Clarke (D-Ward 1) and Rolark - are lawyers, Dixon is a law school graduate.

Moreover, the city has a more complicated and abundant legislative agenda then do county councils because the D.C. City Council enacts the equivalent of city, county and state legislation.

By comparison to the city, the Maryland General Assembly has more than a dozen persons whose primary task is drafting and analyzing legislation. The Montgomery and Prince George's County councils have three persons each with the primary task of drafting bills - the same number as the District.

Among the special interest groups with their own legislative branches the Board of Trade many have one of the largest.

Its legislative and fiscal affairs bureau consists of three full-time analysts for District of Columbia, Virginia and Maryland legislation and various attorneys on-call to draft legislation. In addition, more than half a dozen registered lobgyists assist the bureau.