The Justice Department unveiled yesterday extensive new details of its use of the USA Patriot Act in a bid to shore up support for the embattled anti-terrorism law, asserting that it has helped thwart al Qaeda plots and led to scores of criminal convictions since the Sept. 11, 2001, attacks.

According to a 29-page report to Congress released by Attorney General John D. Ashcroft, Justice Department terrorism investigations have resulted in charges against 310 people and have yielded 179 convictions or guilty pleas. The report says the Patriot Act was central to those cases.

The report also chronicles numerous instances in which the law has been used in traditional criminal investigations, from child pornography prosecutions to the rescue of a kidnapped 88-year-old woman. Ashcroft and other Bush administration officials had not previously revealed the extent to which law enforcement authorities were able to investigate such crimes under the expanded powers provided by the law.

"This report is an unprecedented compilation of dozens of real-life cases from across the country in which the FBI and other law enforcement officials have used the tools of the Patriot Act to protect America's families and communities and even to save lives," Ashcroft said after meeting with House Judiciary Committee Chairman F. James Sensenbrenner Jr. (R-Wis.).

The report comes less than a week after Republicans narrowly defeated a proposal in the House to prohibit the FBI from using the law to obtain library and bookstore records. GOP leaders, under intense pressure from the White House, prolonged a vote for 23 minutes Thursday in a bid to sway enough dissident Republicans to produce a tie vote, which killed the measure.

The Patriot Act, passed overwhelmingly by Congress in the weeks after the 2001 terrorist attacks, gave the government significant new powers to conduct searches and surveillance in terrorism investigations and allowed more information sharing among law enforcement agencies.

The release of the report is part of an effort by the Bush administration to bolster support for the law, some of whose sections are scheduled to expire next year. President Bush on Monday called on Congress to renew those provisions, and Treasury Secretary John W. Snow said yesterday that the law has "dramatically increased our ability to choke off terrorist monies."

Democrats and civil liberties groups, some of whom have long criticized aspects of the law, decried yesterday the extensive use of the Patriot Act for non-terrorism cases. They noted that the report does not mention some of the law's most controversial provisions. For example, Ashcroft declined to say yesterday whether the Justice Department has made use of the section allowing the FBI to obtain business records without a traditional search warrant, information that is classified. As of last summer, when Ashcroft last reported on the use of the new powers, the government had not employed that provision.

Sen. Patrick J. Leahy (Vt.), ranking Democrat on the Senate Judiciary Committee, said in a statement that "the real issue now is how the Patriot Act should be improved to satisfy civil liberty concerns while keeping our country safe."

The Justice Department report says that the Patriot Act was crucial in the prosecution of suspected members of al Qaeda cells in Lackawanna, N.Y., and Portland, Ore., and that it allowed authorities to more easily prosecute dozens of defendants for allegedly providing "material support" to terrorist groups. The report outlines lesser known prosecutions that it characterizes as related to terrorism, including cases involving the Islamic Resistance Movement, a Palestinian group also known as Hamas, and the rebel group FARC in Colombia.

The report provides as examples lengthy accounts of non-terrorism cases in which the Patriot Act played a central role, including investigations of a couple who allegedly defrauded widows and orphans, and of an Indiana man accused of filming the sexual abuse of his 13-year-old daughter. Sensenbrenner highlighted the case of the Wisconsin woman, 88, who was kidnapped in 2003. She was rescued after officials used the Patriot Act to obtain information from Internet service providers.

But Anthony D. Romero, executive director of the American Civil Liberties Union, said the examples indicate that "the Patriot Act went too far too fast, and gave law enforcement officials too much power that had nothing to do with terrorism."