Glimp Professor of Economics Edward L. Glaeser, who has frequently spoken out in Summers’ defense, said on Wednesday that the issue of anti-Semitism was “never the slightest thing on my mind” during the crisis that forced Summers out.

It was Glaeser who helped revive the charge last month, when he told The Crimson that a magazine exposé on fraud allegations against Summers’ friend and fellow economist Andrei Shleifer ’82 was “a potent piece of hate creation—not quite ‘The Protocols of the Elders of Zion,’ but it’s in that camp.”

Glaeser said on Wednesday that he regretted making the comparison, which recalled a notorious anti-Semitic hoax that first appeared in a Russian-language newspaper in 1903. The similarity he meant to point out, Glaeser said, was “that people use defamatory information for their own political objectives.”

“I spent a lot of time in the last week apologizing about this, and just feeling awful,” he said.