CHICAGO (NYTIMES) - It was a video clip watched around the world: A screaming doctor, forcibly yanked from his seat by an officer, who dragged the man down the aisle of a United Airlines jet.
As passengers cried out in horror, two other officers followed down the aisle at the man's feet. They were draped in black jackets with one word stitched in white capital letters across their backs: "POLICE".
But on Wednesday (July 12), more than three months after the episode, the Chicago Department of Aviation conceded that their security officers were not actually police officers and that the uniforms had been "improperly" marked.
It vowed to remove the word from uniforms, vehicles and other insignia in the coming months.
The change represents, perhaps, the most concrete new initiative undertaken by the department in response to the April 9 dragging that roiled United Airlines and that resulted in a legal settlement and four people being placed on leave.
In a 12-page review released on Wednesday, its author, Ms Ginger Evans, the commissioner of the Chicago Department of Aviation, called the situation a sequence of "completely unacceptable" events and suggested that part of the problem was that her security officers had even boarded the plane in the first place.
The report sought mostly to clarify the distinction between the responsibilities of airport security officers and Chicago Police officers - a distinction the report said had been blended and blurred over the years, thanks in part to "old and incorrect policy documents".
Under a new directive, airport security officers such as those who removed the passenger, Dr David Dao, will be sent onto planes only to respond to a disturbance when Chicago Police requests them.
A city ordinance that will go into effect this month (July) will also - with a few exceptions - prevent security officers from removing passengers from an aircraft, said Ms Lauren Huffman, a spokesman for the Chicago Department of Aviation.
"Really, it should be law enforcement that is boarding a plane in most situations," Ms Huffman said in a telephone interview.
"There perhaps was some internal confusion of roles. And we want to be clear to the public," she said.
Most of the fallout from the ugly episode has so far been shouldered by United - including reaching a settlement under which it paid an undisclosed sum to Dr Dao - which has taken responsibility for what happened on Flight 3411.
But in Wednesday's report, Ms Evans wrote that the city of Chicago's Office of the Inspector General had conducted a "disciplinary investigation" into the three officers and one supervisor involved in the episode, and pledged that the Chicago Department of Aviation would "take action" in response.
The department administers Chicago's two major airports, including O'Hare International, where the dragging occurred.
The department had also begun a review of security-officer training, started updating its field manual and was preparing a "comprehensive review" of its policies, according to the report.
Mr Thomas Demetrio, a lawyer for Dr Dao, said in a telephone interview that he did not believe a similar incident would happen again.
"I'm just happy that the city of Chicago recognised that people need to be treated with respect and dignity," he said.