(FORTUNE Magazine) – This is getting livelier than Clarence Darrow's courtroom battle with William Jennings Bryan in 1925's famous Scopes Monkey Trial. The fight between attorney and Harvard law professor Alan Dershowitz, 53, and Harvard law school alum turned journalist James Stewart, 40, has spilled over from the pages of the Wall Street Journal, where Stewart is an editor, into paid ads in the New York Times. At issue: Stewart's book Den of Thieves, which has heaps about jailed junk bond king Michael Milken. Dershowitz, who is Milken's attorney and who also won an appeal by Claus von Bulow against a conviction for trying to murder his heiress wife, says Stewart has been waging an unfounded smear campaign against his client in articles that predate the book. The Journal excerpted the book, and then ran two pieces by Dershowitz, each accompanied by Stewart's rebuttals of Dershowitz's rebuttals. Next thing, Dershowitz paid $43,000 and the Milken defense fund chipped in another $24,000 for two ads in the Times. In one he complained about the book, in the other about the Times' favorable review by Michael Thomas, a former Wall Streeter himself and now a curmudgeonly columnist. (FORTUNE liked the tome too; Books & Ideas, October 21.) Says Dershowitz: ''I'm simply trying to level the playing field.'' Says Stewart of the ad campaign: ''I'm not going to dignify it with a response.'' Dershowitz, of course, is conducting Milken's appeal against a ten-year sentence for racketeering and securities fraud. Beyond that, Dershowitz still could be smarting over a report by Stewart in a 1984 Journal article that said he once didn't bother to fully prepare for a class at Harvard Law School and used an audio-tape player instead. Dershowitz says he did use one -- but only for instructional purposes. Students heard cops eliciting a confession, but the professor says he based that lesson on the recording.