Large Los Angeles law firms have poor diversity records, with the numbers of female, black, Latino, Asian and gay partners and associates lagging significantly behind their representation in the city's population, according to a study released Wednesday.

The 17 Los Angeles-area firms in the report have three or fewer African American partners; all but one have three or fewer Latino partners, and half have three or fewer Asian American partners, placing the percentage of partners in those ethnic groups at less than 5%. In contrast, 2005 census data show that African Americans, Latinos and Asian Americans constitute 9.7%, 46.8% and 13.1% of the population in Los Angeles County.

Although more than half the county's residents are women, no firm has nearly that percentage of female partners; the firm with the highest female representation among partners has 27.7%. Moreover, at every firm surveyed, women are significantly less represented as partners than as associates. For example, fully 60% of the associates at one firm are women, but only 14.6% of its partners.

The highest percentage of African American partners at a firm in Los Angeles is 4.6%, while the top percentage of Latino partners is 8.2%. The highest percentage of Asian American partners is 11.1%, and the top percentage of partners who are openly lesbian, gay or bisexual is 7.4%.

Three firms have no African American partners, one has no Latino partners, one has no Asian American partners, and three firms have no publicly declared lesbian or gay partners.

The study was released by Law Students Building a Better Legal Profession at a news conference in Washington, D.C., and online.

The group took self-reported figures provided by the firms to the National Assn. of Law Placement and aggregated them. Detailed information on firms in Los Angeles, Northern California and New York can be found on the group's website, http://refirmation.wordpress.com

The report includes figures for the percentage of lawyers at the firms who do pro bono work and the average number of billable hours for associates at the firms. Those figures vary widely.

Similar percentages were found in other large metropolitan areas. Women make up less than 25% of the partners at all 74 firms surveyed in New York with 100 or more lawyers, while 27 of those firms have no Latino partner, 25 have no African American partner, and 21 have no Asian American partner.

Of 46 firms surveyed in Washington, 17 have no Latino partner, seven have no African American partner, and 13 have no Asian American partner. The picture is somewhat better in the San Francisco Bay Area. Still, only 7 of 31 firms have 25% or more female partners, with the highest figure 32.7%.

Andrew Bruck, co-president of the law student group, emphasized that all the information came from figures that the firms provided. The study deals only with law firms that employ 100 or more attorneys in each market.

"Most students think big firms are indistinguishable, but they're not," said Bruck, a third-year student at Stanford Law School. "Our report helps students see the difference between their potential employers. By providing this information . . . we're helping students make better-informed choices about where they want to work after graduation."

Katherine Reilly, vice president of the Harvard Women's Law Assn., said she thought the report could have broad ramifications. She said students at prestigious law schools "are in a powerful position to positively influence the legal profession by making educated choices early in their careers about the kinds of law firms for which they want to work."

Reilly, a second-year student, said she was not surprised by the figures showing a significant drop-off between the percentage of female associates at large law firms and the percentage who make partner, known as the "opportunity gap."

Those numbers "say something about the atmosphere at the firm regarding support for having a life and family outside the office," Reilly said.

Stanford law professor Michele L. Dauber, who supervised the students' research and compilation of the data, said the research "sends a message to America's law firms that is loud and clear: The best law students want to work at the firms where they have a fair chance at promotion and where it is possible to work hard and enjoy a family life. It's about time students collected this kind of basic information about law firms and began to vote with their feet."

Dauber said the students were preparing a book with all the data and rankings and planned to send the material to Fortune 500 companies who use the services of the big law firms, in the hope that this action also will stimulate change in hiring and promotion practices.

Bruck and Reilly said the students who organized the project are not advocating that law schools bar firms from recruiting at law schools because they have bad percentages in any particular category or in the aggregate. Still, they expressed hope that the data would have an effect.

"We are hoping firms don't want to be known as places where women don't make partner," Bruck said.

"We hope students will look at the data and start asking tough questions."