Theodore B. Olson, the forceful conservative litigator who served as the Bush administration's top attorney for three eventful years and who lost his wife in the terrorist attacks of Sept. 11, 2001, said yesterday that he is stepping down as U.S. solicitor general.

Olson, 63, said in an interview that he wanted to announce his departure before the U.S. Supreme Court issues a flurry of decisions next week on cases ranging from U.S. detention policies to an Internet pornography case. "It's going to be a big deal next week," he said. "I wanted to do it now before the term is up and everyone is dispersed."

"I had planned every year to consider what I was going to do in June when the court is done with arguments," Olson said. "I have been here three years, and it seemed to be the right time."

Olson, a hero of the modern conservative legal movement, gained national fame in 2000 when he represented George W. Bush before the Supreme Court in Bush v. Gore. The court's ruling halted the Florida vote recount and resulted in Bush capturing the presidency.

Olson's nomination as solicitor general the next year prompted fierce opposition from Senate Democrats, who viewed him as an arch-conservative and questioned his role in various challenges to former president Bill Clinton by conservative activists. But Olson also engendered praise from legal scholars on both sides of the political aisle, including liberal Democrats such as Laurence H. Tribe, the Harvard law professor who argued against Olson in the first round of the Supreme Court dispute over the 2000 elections.

Olson has argued 26 cases before the Supreme Court as solicitor general, winning 20 of the 23 that have been decided to date. Two are pending, and one was dismissed with no decision on the merits.

Since the terrorist attacks, Olson has been at the forefront of the Bush administration's legal campaign against terrorism, defending expanded surveillance powers under the USA Patriot Act and arguing for extensive presidential control over detainees. Olson's unusually public role in the campaign had a tragic personal dimension: His wife, Barbara, a lawyer and frequent television commentator, was aboard the jetliner that crashed into the Pentagon.

Attorney General John D. Ashcroft said in a statement that Olson "is among the finest individuals it has been my privilege to know," calling him "a dedicated patriot who brought unbridled energy and enthusiasm, along with brilliant legal acumen and peerless dedication to his office and to Justice."

While his departure at the end of the Supreme Court term is not a surprise, Olson is known inside the Justice Department to be unhappy that he was not informed about controversial memos authored by the Office of Legal Counsel on the use of harsh interrogation methods on detainees overseas, according to a department official who declined to be identified because of the sensitivity of the issue.

Olson was among the last remaining Justice officials who helped craft the administration's controversial and aggressive legal strategy on terrorism after the attacks. His departure closely follows the announcement last week that the head of the OLC, Jack L. Goldsmith III, also is resigning.

Olson said he has not decided whether he will return to the firm of Gibson, Dunn and Crutcher, where he has spent much of his legal career.

The Supreme Court is expected to issue highly anticipated rulings next week in three cases argued by Olson's office. Two involve U.S. citizens Yaser Esam Hamdi and Jose Padilla, who were declared enemy combatants by Bush and have been held in a military brig without charges. In another case, the court will consider whether U.S. courts have jurisdiction over detainees held at the military prison in Guantanamo Bay, Cuba.

Researcher Lucy Shackelford contributed to this report.

Theodore B. Olson has won 20 of 23 Supreme Court cases so far.