A public education poster at Metro's McPherson Square station urged riders to report sexual harassment. (Kery Murakami/(For Express))

On an Orange Line train approaching L’Enfant Plaza last week, a woman sleepily texted with a friend.

“I’m so tired,” she complained as she rode during the morning rush hour in a car crowded with other commuters — and apparently at least one pervert. Suddenly, a close-up picture of a penis appeared on the screen of her iPhone, sent to her via AirDrop by someone close by.

The feature for sharing files on Apple devices gives users the option to accept or decline a file being sent to them. Unfortunately, it also shows a preview of the file.

It was the second time in a month that a picture of a penis appeared on her screen while she was on Metro, the woman said later by email.

The first time, she hit decline on her screen over and over. More than 10 times. But the penis kept reappearing until she got off the train and turned AirDrop off.

The woman, whose name isn’t being used to protect her privacy, looked around the crowded car for a sign of who’d done it. But she saw no one ogling her or laughing. Just the blank faces of the morning commute.

Hours later, she was still upset.

“WHY CAN’T I RIDE THE METRO IN PEACE,” she vented on Twitter, with a photo of what had appeared on her screen.

Judging from Twitter, this has happened to several women on Metro in recent months.

“I’m on @wmata on the way to work and someone just tried to airdrop me a d--k pick," a woman named Jenna posted on March 8.

“I felt dirty,” she later told the local news site DCist. “It’s not like someone actually grabbed me or touched me, but it’s in my head. My day is now colored by that.”

Creepier still, she knew the man had to be within AirDrop’s roughly 30-foot range. “If someone is willing to do that, that’s not a person that I necessarily want to be in a metal tube under the ground with for 20 minutes,” she told DCist.

In November, another woman said in a tweet that she actually met the man who’d sent her a photo of his penis. She had just declined the photo, when a man standing nearby asked why she’d rejected it.

“I told him I was not interested in his nudes,” she wrote, adding “SMH,” short for “shaking my head.”

The District isn’t the only place where dirtbags are using technology for their perversions.

A spate of recent incidents in New York prompted two city council members in November to propose explicitly making cyber-flashing a crime, punishable by a year in jail.

A problem, say cybersecurity experts like Nathan Freitas of Harvard University’s Berkman Klein Center for Internet & Society, is that AirDrop can be a convenient tool for creeps. "There is no real record or proof of who the sender was, unfortunately,” he said.

Metro did not respond to an inquiry about these incidents, but Freitas said there’s not much the agency can do about them. “AirDrop and other file transfer mechanisms use the same frequencies as standard Wi-Fi and Bluetooth, so any attempted signal jamming would also block headphones, smart watches and perhaps even some of the system used by the transit authority,” he said.

He was puzzled that AirDrop is set up so that images appear without a chance to block them. ”Ultimately, Apple and others need to consider bad actors more seriously in their design process, just like Facebook and Twitter,” Freitas said. Apple had no comment.

In the aftermath of the Orange Line incident, a number of people responded to the woman’s tweet letting her know she could change AirDrop’s settings to enable sharing with just her contacts, and not with anyone within range. Or she could turn the feature off.

“Yes, my AirDrop should have been turned off, but hey, I forget that it’s even on my phone until the time comes time to use it,” she told us by email.

But there’s also an element of blaming the victim to that sort of response.

“I shouldn’t have to worry about receiving pictures like that every time I take the Metro to/from work, nor should anybody else,” she said.

Got a story about riding Metro or have a question? Send it to kery.murakami@washpost.com or @theDCrider.

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