Liberals watched anxiously as the Federalist Society (search) rose from a loosely organized conservative legal organization on a few law school campuses to become a Washington powerhouse with influence in the White House, Congress and various federal agencies.

Now they are fighting back.

The American Constitution Society for Law and Policy (search) is having a coming-out party this week. For three days starting Friday, law students and attorneys will hear speeches by Supreme Court Justice Ruth Bader Ginsburg and Sen. Hillary Clinton, D-N.Y.; attend discussions on the environment, abortion, gay rights, government surveillance, human rights and other subjects; and mingle with dozens of top legal scholars and judges.

It's not all heavy lifting. There also is a Janet Reno Dance Party (search) on Saturday night.

The nonprofit association got under way two years ago after President Bush took office and began filling top government jobs and judgeships with members of the 21-year-old Federalist Society for Law and Public Policy Studies. The Federalist Society has an extensive network of conservative lawyers and judges.

"The conservatives have been shrewder in organizing and the liberals have woken up," said Jamin Raskin, a liberal law professor at American University.

Like the Federalist Society, the American Constitution Society is focusing on recruiting young members on law school campuses. Neither group lobbies or takes positions on legislation. Both have full-time offices in Washington.

"Imitation is a form of flattery. The Federalist Society should be flattered," said Federalist Society member John Baker, a law professor at Louisiana State University.

The Constitution Society event, less glitzy than the affairs of the Federalists, will be their first convention. It is expected to draw more than 400 people.

The last Federalist Society convention featured Attorney General John Ashcroft and Supreme Court Justice Antonin Scalia, who was involved in the society during its founding.

The Federalist Society has student chapters on about 150 law school campuses and lawyer chapters in 60 cities, from Anchorage, Alaska, to New Orleans. The American Constitution Society has started 80 law school chapters and has lawyer chapters in four cities: Chicago, Los Angeles, Minneapolis and Washington.

About 30,000 people are involved in Federalist Society activities, compared with 6,000 for the Constitution Society.

The two groups are mainly funded with donations from foundations, law firms and individuals, although the Federalist Society has also received contributions from companies such as Microsoft Corp. and Pfizer Inc.

Leaders of the Constitution Society prefer to call themselves progressives, not liberals.

"This is an organization that allows for different voices to be heard and the issues to be debated in a lot of ways without the political correctness that you see in the Federalist Society," said Eric Holder, a Washington lawyer and former U.S. deputy attorney general in the Clinton administration. "They are a little too exclusionary."

Holder said the group will deal with issues that affect all people, like discrimination, consumer rights and free speech.

Eugene Meyer, president of the Federalist Society, said that they carefully balance forums, with conservative and liberal speakers. The society has jointly sponsored campus events with the Constitution Society, he said, and wishes the newer organization well.

"The more discussion and debate that's civil and serious, the better," he said. "They have the potential to encourage more civility on the left. I think that would be a good thing."

A founder of the Constitution Society, Walter Dellinger, acting solicitor general in the Clinton administration, said conservatives have been more focused. "If you lack ideas and lack intellectual rigor, you're going to end up on the losing side of the great legal debates."