Typically, history professors aren’t the bad boys of the university scene. Leave that to the English-department prima donnas. So how did such distinguished scholars as Steven Ambrose, Doris Kearns Goodwin, and Joseph Ellis end up competing for headlines with Tara Reid?

In “Historians in Trouble: Plagiarism, Fraud, and Politics in the Ivory Tower,” (New Press, 260 pages, $24.95), Jon Wiener, a professor of history at the University of California at Irvine, looks at a dozen cases of recent misconduct. Mr. Wiener revisits the saga of the well-publicized plagiarists, Stephen Ambrose and Doris Kearns Goodwin. He examines obscure offenders like historian Edward Pearson, whose book about Denmark Vesey was so riddled with errors it was withdrawn from publication. And he writes about Mr. Ellis, a history professor at Mount Holyoke, who for years regaled his students with made-up stories about serving in Vietnam.

The offenses Mr. Wiener treats are wide-ranging. So, too, are the fallouts. He notes that, while some debates about historical scholarship blow up into national news stories, others fade away with hardly a mention in the school newspaper. But what this says about scholarly integrity in America, Mr. Wiener isn’t sure of. “There is no single lesson to be found or meaning to be discovered in the twelve cases examined in this book,” he writes.

Nevertheless, he is happy to dish out several different lessons – which, in the absence of a central argument, dissolve into the surrounding hot water like biscuits at teatime. We learn that historians are human (yes, human!) and susceptible to the corrupting lure of lucre. “Historians do not work in ivory towers,” writes Mr. Wiener. “They compete in markets like everyone else.” He also reminds his readers to “take good notes.”

Somewhere along the way, Mr. Wiener stumbles onto a vast rightwing conspiracy. Amid the controversies, he sees a double standard: If a conservative history professor is accused of fraud, he can claim to be the victim of political correctness, and conservative Pooh-Bahs are sure to rally in his defense. To hear Mr. Wiener tell it, his conservative colleagues could get away with making footnotes out of Swiss cheese.

Liberal history professors, by contrast, are constantly under attack from a mob of knuckle-dragging conservatives. As proof he presents the case of historian Michael Bellesiles who in 2000 published “Arming America,” a study of gun ownership in colonial times. Mr. Bellesiles’s book claimed that, contrary to prevailing wisdom, few Americans prior to the Civil War owned firearms.

At first, critics praised the work, speculating that it might reframe the national debate on gun control. Under closer scrutiny, Mr. Bellesiles’s findings fell apart. Readers discovered that he had falsified crucial data supporting his arguments. When pressed, he tendered a variation of the old dog-ate-my-homework defense, explaining that a flood had destroyed his notes. He also claimed gun advocates were attacking his work for political reasons.

Who should swoop in to defend Mr. Bellesiles? Enter our author (stage: left). In the end, Mr. Wiener does exactly what he accuses conservatives of doing – a bit of ungainly mental gymnastics to excuse a politically likeminded scholar of his wrongdoings. “Where power is exercised, historians are rewarded and historians are punished,” writes Mr. Wiener. “The real need over the longer term is to find ways to counter the excessive power of right-wing advocacy groups.”

As it turns out, sometimes historians lie. Sometimes they plagiarize. And sometimes they simply write lousy books.

For an actual thesis (and a lucid one at that) explaining the same phenomenon, turn to Peter Charles Hoffer and his recent work, “Past Imperfect” (PublicAffairs, 287 pages, $26). Rather than view the likes of Mr. Bellesiles through the distorting lens of politics, Mr. Hoffer, a history professor at the University of Georgia, provides a historical perspective.

He begins by noting that “American history is two-faced like the ancient Roman god Janus.” On the one hand, he argues, there is the heroic version of American history, which celebrates our founding fathers, their vision of democracy, and the progress of the nation. On the other there is a critical version, which chronicles ruthless European settlers who displace the natives, institutionalize slavery, and exploit the working class.

Mr. Hoffer argues that, ever since the 1960s, the gap between celebratory, popular history and academic, critical history has continued to widen. Popular history writers such as Ms. Goodwin and Mr. Ambrose are caught between the expectations of the public (which wants tales of heroism, sweeping narratives, and dramatic flair) and the expectations of their cloistered colleagues (who want precise methodologies, statistics, and rigid distinction between primary and secondary sources). Historians who try and straddle the chasm often end up toppling headlong into the scholarly abyss.

Mr. Hoffer is no apologist for sloppy history. He tears into Ms. Goodwin, Mr. Ambrose, and Mr. Bellesiles with prosecutorial relish. Yet he also pounces on the progenitors of esoteric critical monographs for ignoring the public’s longing for readable history. The solution, he argues, requires reclaiming some middle ground. “Because American history is two-faced, everyone who undertakes to write about or teach American history in a thorough manner has an almost intolerable burden,” he writes, “to balance a critical approach and a rightful pride.”

Mr. Gillette last wrote for these pages on childhood in America.