The American Institute of Architects yesterday settled an antitrust suit filed by the Justice Department alleging that the association tried to discourage price competition for architects' services.

Representatives of the 55,000-member association signed a consent decree in which they agreed not to adopt policies dictating pricing practices to members. They also agreed to educate their members about antitrust laws.

The settlement ends a nationwide investigation of the pricing practices of architects that lasted 4 1/2 years. It is the second time the AIA has been accused of violating antitrust law. In 1972, the AIA signed a consent decree that alleged violation of the pricing statutes.

The association did not admit guilt in either instance. "We take the position that we did not violate antitrust laws," said David K. Perdue, associate general counsel of the association.

The complaint alleged that the AIA entered into an unlawful agreement to prohibit architects from bidding competitively for work, offering discounted fees or providing free services. The Justice Department complaint cites a written policy that was adopted by the association's Chicago chapter in 1984 that prohibited such practices.

Washington architect Hugh Newell Jacobsen said yesterday that architects have traditionally felt that they should be chosen for characteristics other than price.

"It's a thing in the rules ... that you never discuss fees," Jacobsen said matter-of-factly. "If you interview us, select us for our ability, our experience or our necktie, but never talk about fees. Don't come in and have us tell you our design philosophy and then ask us our fee.

"Of the men and women whose work I admire, we'll never do it," he said of the practice of quoting fees for a building when there is a competition for architects.

The Justice Department consent decree does not require architects to engage in competitive bidding, according to Perdue. It simply says the institute may not take actions or adopt policies that restrain them from giving price quotations if they choose to.

Architects charge for their services in a number of ways. Some charge a percentage of the total value of the project. Others charge a lump sum for their work, an hourly fee or a combination.

Washington architect Ted Mariani, who handled the negotiations on the settlement for AIA, said yesterday that the agreement would have little real impact on architects' lives.

"I can still refuse to get into a competition that involves price," said Mariani, of Mariani & Associates.

"If a client calls and wants a price to design a building, I won't do that. I don't want to get into a price competition," he said.

However, he said some architects had gotten careless about antitrust issues over the last several years.

"If I get together with two or three architects and say 'I don't think we should compete on price,' that's a problem."