Two state troopers violated agency policy last year when they improperly arrested a parking lot attendant who had booted their unmarked vehicle in Uptown New Orleans. But only one of the troopers received any discipline, and his punishment was reduced from a proposed suspension to a letter of reprimand, State Police records released this week show.

An internal investigation left no doubt among State Police brass that Sgt. Joseph Patout and Master Trooper Christopher Treadaway had been out of line when they arrested Brandon Hardeway, an attendant in a private parking lot who insisted the troopers pay a $90 fee to have the boot removed.

The troopers, who had parked in the lot while they ate lunch at Kyoto, a sushi bar on Prytania Street, accused Hardeway of obstructing their official duties, as the booting incident delayed a shopping trip to Office Depot, where they planned to buy supplies for an undercover human-trafficking operation.

Hardeway, who filed a federal civil rights lawsuit against State Police this month, was released from custody only after higher-ranking State Police officials determined he had not broken any laws and that he had been within his rights to boot the troopers’ vehicle.

The internal affairs inquiry concluded that Patout and Treadaway violated a policy that requires troopers to “maintain a competency level sufficient to properly perform (their) duties” and that they showed a “lack of knowledge in the application of laws required to be enforced.”

Patout also was found to have run afoul of a policy forbidding troopers from using their badge “for personal or financial gain,” a finding stemming from his decision to place his State Police placard in the vehicle’s dashboard in an effort to avoid being booted.

Though both troopers broke department rules, the agency disciplined only the higher-ranking Patout.

Lt. J.B. Slaton, a State Police spokesman, said Treadaway was found to have “reacted” to Patout’s actions in the parking lot.

“As a supervisor, he should have known better,” Slaton said, referring to Patout. “We took this very seriously.”

Asked how Patout avoided suspension, Slaton said the sergeant, in the end, took “full responsibility for the entire incident.”

“Although I believed that my actions were justified at the time, I feel if I had considered other options, I likely would have disputed the boot at a later time,” Patout wrote in his account of the incident, adding that he never used profanity or acted “less than professionally toward Mr. Hardeway.”

Lt. Col. Charles Dupuy, the agency’s deputy superintendent, who initially proposed suspending Patout, warned him that “any future violations of this or any nature may result in more severe discipline, including termination.” Both Patout and Treadaway had previously been disciplined for crashing agency vehicles, according to State Police records.

The parking lot run-in happened on April 5, 2014. Patout and Treadaway had been assigned to a human-trafficking detail in New Orleans connected to a WrestleMania event at the Mercedes-Benz Superdome. The troopers acknowledged parking in a private lot reserved for other businesses, but they said they couldn’t find any open street parking.

Patout, noting Hardeway had not booted an unmarked New Orleans Police Department vehicle in the lot, asked the attendant to “cut (him) some slack” and remove the boot, records show. Hardeway checked with his boss at Premier Parking Enforcement and told the troopers they’d have to pay the $90.

“Mr. Hardeway explained to Sgt. Patout that his company had an agreement with NOPD and they do not boot their police units,” the internal affairs report says.

Several higher-ranking State Police officials arrived at the lot, where Maj. Paul Edmonson ordered that Hardeway be “un-arrested” and removed from the back of a State Police vehicle, the records show.

State Police finally paid the removal fee using investigative expense funds — money Patout was told he had to reimburse, records show.

Hardeway’s boss told investigators that the troopers “would be in for a rude awakening” because the entire incident was recorded on Hardeway’s body camera, according to the 19-page report, which The New Orleans Advocate obtained in response to a public records request. That video was never turned over to State Police, the report says, though it could play a role in Hardeway’s lawsuit.

Follow Jim Mustian on Twitter, @JimMustian.