It is not always the corrupt politicians who do the most harm. The stupid ones can be a bigger menace.

One way to test this proposition might be to compare the legacies, say, of two mayors: one crooked and one inept. But such comparisons are not totally reliable, for each era brings different challenges and temptations. A hero of the palmy days may be found wanting when the chips are down.

Fortunately, we do not need to weigh the shortcomings of disparate administrations to establish the truth that it is the fools we must fear. All we need is one politician who came up short in both the integrity and brains departments, so we can determine which deficiency left the public more to rue. Ray Nagin fits the bill perfectly.

Nagin, the first New Orleans mayor to be convicted for dipping into the cookie jar, is a resident at the federal pen in Texarkana, Texas. The prevailing view is that he was lucky Judge Ginger Berrigan gave him only 10 years, and there is no calculating the extent of the damage he inflicted on the city by pocketing sweeteners from government contractors.

Still, his successor, Mitch Landrieu, is evidently free of the larcenous tendencies that brought Nagin down, and their effects are wearing off. We are still paying the price for Nagin’s lack of smarts, however.

The mere fact that Nagin ruined his life for the sake of relatively small payoffs may be regarded as evidence enough of muddled thinking, but the true measure of his goofiness is the appointments he made as mayor.

Putting a trumpeter in charge of the public libraries always did seem one of Nagin’s quirkiest choices, and Irvin Mayfield, after being made chairman of the board, managed to run many experienced hands out of the system.

After leaving that job, he, along with his sidekick Ronald Markham, remained a member of the foundation that raises money for the libraries. In 2012 and 2013, the foundation handed almost $900,000 to Mayfield’s New Orleans Jazz Orchestra.

Donors, who may have thought they were helping to bring the joys of literature to the masses, would probably not have agreed, if offered the choice, to divert their money. Mayfield, a recording star and Grammy winner with all manner of lucrative gigs on the side, hardly needs charity. Indeed, he could probably rub along without the $148,000 a year he pockets from NOJO, which also pays Markham a $100,000 salary.

Clearly Markham and Mayfield could not have wound up on both the giving and receiving ends of other people’s money had their colleagues on the foundation board fulfilled their fiduciary responsibilities. But Mayfield always seems to get his own way.

So it was when he chaired the library board, which failed to make the minutes of its meetings public as state law demands. Only when legal action was threatened did the board type up and release the minutes, which did not, however, record any vote tallies. That was not necessary, Mayfield explained, because he had won the board’s unanimous support on every issue since he took over.

Mayfield, as library board chairman, always made it clear that rules did not apply to him as, for instance, when appointing a non-librarian as chief executive, in defiance of the city charter, and attempting to supplement her salary with foundation money, which is forbidden by statute.

If the rest of the library board was therefore superfluous, the same was true at the foundation. The board there formally acknowledged as much in passing a resolution giving Mayfield authority to “sign any and all acts, agreements, contracts and documents” that “he in his sole and uncontrolled discretions deems necessary.” Mayfield promptly plopped the library money in his jazz orchestra account.

A complete list of Nagin’s ill-considered and disastrous hires would fill a book. Pride of place would have to go to Ed Blakely, his choice to lead the city’s Katrina recovery, who spent half his time spouting gobbledygook and the other half badmouthing the local populace.

Nagin’s ineptitude in choosing aides was apparent from the get-go. His first CAO, Kimberly Williamson Butler, was ousted and later wound up in the slammer for three days on a contempt charge. On her release, she compared herself to Rosa Parks, Martin Luther King Jr., Nelson Mandela and Ghandi.

After Blakely left town, he wrote a book in which he compared Nagin to Abraham Lincoln.

Whether Mayfield reminds himself of any great figure is unknown — he has been curiously quiet of late — but, given his fondness for blowing his own trumpet, maybe the Angel Gabriel would be a good fit. Unless that’s aiming too low.

James Gill’s email address is jgill@ theadvocate.com.