When it comes to churning out law deans, Yale Law School has a slight edge over Harvard Law School, having educated 26 of the deans serving now compared to 23 who passed through Harvard.

That’s one of the tidbits Mississippi College School of Law Dean Jim Rosenblatt dug up in the process of creating an online repository of information about law deans, which he calls Rosenblatt’s Deans Database. He conceived of the project two years ago.

“The question was being asked, ‘How long do deans serve?’ ” Rosenblatt said. “ I thought this was something I could assist the legal community with. I hope it’s of some use to dean search committees and to other deans, so they can see how they are moving up the seniority ladder.”

Rosenblatt found plenty of other interesting statistics, including that the longest-serving dean is John O’Brien of the New England School of Law, who’s been in the job more than 25 years. The average tenure for sitting law deans is slightly more than four years and the median tenure 3.24 years.

The online database allows users to search in a variety of ways and includes some presorted data points, like which schools have produced the most sitting deans. Harvard and Yale — the usual suspects — top that list. Yale’s class of 1979 was particularly prolific, producing four deans.

Some lower-ranking schools sent more alumni into deanships than higher-ranked competitors. For example, the University of Michigan Law School is ranked No. 9 by U.S. News & World Report but counts 14 deans as alumni. That earned it the No. 3 rank — better than Stanford Law School, Columbia Law School and the University of Chicago Law School.

Rutgers School of Law-Newark was ranked No. 86 by U.S. News but has three alumni serving as deans — the same number as the No. 11-ranked Duke Law School, No. 15 Vanderbilt University Law School and No. 17 University of Southern California Gould School of Law.

According to the database, four deans have served for more than 20 years and another 32 for a decade or more. After O’Brien, the next longest-serving dean is the Thomas M. Cooley Law School’s Don LeDuc, followed by Baylor University School of Law’s Bradley Toben.

The past two years have seen an unusually high amount of turnover, Rosenblatt said, due in part to the tough economic and recruiting climate. “I think there has been more change-over in deans than in any other two-year period,” he said.

According to his database, 19 schools now have interim deans.

Contact Karen Sloan at [email protected].