The Green Bag has created about one bobblehead a year, starting with Chief Justice Rehnquist in 2003 and adding more mostly in reverse order of seniority. It has not yet reached the three Yale graduates on the court: Justices Clarence Thomas, Samuel A. Alito Jr. and Sonia Sotomayor. Mr. Davies, a law professor at George Mason University, said a Justice Thomas doll was planned for next year.

The journal makes 1,000 to 2,000 of each bobblehead. They are not for sale. “We make no promises about when we will make them or who will get them,” the journal’s Web site says, though subscribers seem to have pretty good luck.

In an interview, Mr. Davies said two words best describe the journal’s bobblehead distribution policy. “Caprice,” he said, “and willy-nilly.” That is frustrating for the aficionados who prize the dolls and have been known to pay thousands of dollars for a single one in online auctions.

The Yale bobblehead collection has some rarities, including early drafts and alternate versions. In one, Chief Justice Rehnquist holds a purple law book. That would not do, Mr. Davies said. “In Supreme Court practice,” he said, “getting things just right is really important.”

The rarest item is a bobblehead of Justice Antonin Scalia featuring allusions to his majority opinions. Only one exists; the official version focuses on his dissents.

In showing two visitors around the Paskus-Danziger Rare Book Room and the vault behind it, Mr. Widener moved easily between the old world and the new one. He spoke excitedly about a new acquisition — an Italian translation of Blackstone’s commentaries on criminal law from 1813. Then, perhaps inevitably, he told a joke.