In the “Harry Potter” stories, no professor of Defense Against the Dark Arts lasts more than a year at Hogwarts, the school of young witches and wizards.

Here in the muggle world, turnover has been almost as high at the Thruway Authority, at least under Gov. Andrew Cuomo.

Since Cuomo took office in January 2011, five different people have held the position of Thruway Authority executive director – including on an interim basis – with a sixth person named earlier this month.

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Michael Fleischer, a holdover from the Pataki administration, announced his resignation during Cuomo’s first year in office, in July 2011. The following month, Cuomo nominated Thomas Madison, a former federal transportation official, to replace Fleischer.

Madison abruptly resigned at the end of 2014 while the authority faced a multimillion-dollar budget shortfall. The New York Post reported at the time that the state inspector general had prepared a “scathing” report about the Thruway’s operations, and a few weeks later the Daily News reported that the IG was investigating prostitution allegations involving Thruway officials.

Bob Megna, a longtime state budget director, took over as executive director of the authority in January 2015, starting out in an interim role. Maria Lehman was promoted to acting executive director in January 2016 when Megna left for Stony Brook University.

Lehman was replaced by Bill Finch, a former Connecticut mayor and state senator, who was appointed to the post in June of 2016. Lehman retired in October 2016 after what was reportedly a disagreement with the Cuomo administration over the pace of a project promoting New York farm products.

Finally, the governor this month announced that he would nominate state Transportation Commissioner Matthew Driscoll as his latest executive director of the authority, which oversees the 570-mile New York State Thruway.  

By contrast, Fleischer held the position for more than eight years before resigning early on in Cuomo’s first term.

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“My only comment is that the high turnover can’t be helpful in terms of the management of the agency or in developing realistic budgets, which are critical for protecting taxpayers and promoting economic growth,” Westchester County Executive Rob Astorino wrote in an email to City & State. Astorino, a critic of the governor who ran against him in 2014, represents a county that has a stretch of the Thruway, including the eastern side of the Tappan Zee Bridge, which carries the Thruway over the Hudson River.

The Cuomo administration did not respond to a request for a comment regarding the turnover at the authority.

The first span of the new Tappan Zee Bridge – renamed the Governor Mario M. Cuomo Bridge – opened on Saturday, but it may take some financial wizardry to figure out how to pay for it. Since the Cuomo administration began pushing for the project there have been concerns about how it will be paid for and whether tolls would have to be raised as a result.

Astorino said he was an early advocate for building the $4 billion bridge and he gives the governor a lot of credit for the latest milestone, but added that “it’s troubling that we have now had a ribbon cutting, and we still don’t know how we are going to pay for the bridge."

Cuomo said recently that tolls would help pay for the bridge starting in 2020, although it’s unclear if Thruway users who don’t cross the bridge would have to pitch in.