THE man wearing a blue shirt and khaki pants stood casually inside a security screening area at a San Francisco airport terminal. As security officers and passengers bustled, he pointed to a woman and took her into the private screening room. Later, he pointed to another woman, and she followed him in as well.

The man, despite also wearing the blue latex gloves used by screeners, was no professional officer, said John S. Pistole, the administrator of the Transportation Security Administration. He was just another passenger with an international ticket.

Mr. Pistole described the encounters for me based on the surveillance video from the international terminal at San Francisco International Airport. Around noon on July 15, the man acted “like a security officer,” Mr. Pistole said, directing two women into the private area for extra screening, for about a minute at a time.

Each woman left the room not exhibiting apparent signs of distress. But an actual screener thought that something was wrong. Only female officers are supposed to accompany women sent into the private room for extra screening, which can include a full-body pat-down. And blue shirt and gloves notwithstanding, the man had no badge or emblem on his shirt, clearly not a screening officer.

The man, whom the San Mateo County Sheriff’s Office identified as Eric Slighton, 53, was arrested, charged with public intoxication, taken to jail and released on bail. He had been scheduled for an arraignment this week, but on Friday, the district attorney’s office said it would not prosecute. “We could not prove the elements of the offense beyond a reasonable doubt,” said Albert A. Serrato, an assistant district attorney.

The police tried to identify which flights any possible victims might have taken or where they might have flown, the sheriff’s office said. But the women have not been found.

Attempts to reach Mr. Slighton, who had a ticket that day to fly to Hong Kong, were not successful. A resident of San Francisco and Hong Kong, Mr. Slighton is a director at Aktis Capital Singapore, a private equity firm. A statement acknowledging the incident by the related Aktis Hanxi Group said, “Mr. Slighton has been granted a leave of absence.” Calls and emails to the group’s offices were not returned.

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