On a summer day at JR Shin-Okubo Station in Tokyo’s Shinjuku Ward, a group of “vigilantes” surrounded a man in front of a ticket gate.

“Why are you watching girls passing by, huh?” one of them, occasionally grinning, asked the man.

The posse accused him of stalking a woman, forced him to apologize in front of a camera and took him to a police box.

The incident appeared in a YouTube video posted on Aug. 20, with the supposed stalker’s face blurred out but with subtitles describing him as a “suspect.”

However, legal experts say the only crimes in the video were likely perpetrated by the YouTuber and his henchmen.

Video clips like these, of people taking the law into their own hands, are increasingly appearing on social media. They target randomly selected, suspicious-looking people in public, and make what they call “citizen’s arrests.”

Their videos often go viral, leading to higher earnings for the posters.

But these videomakers seem lost on certain aspect of the law, including privacy rights.

And under the Criminal Procedure Law, private civilians can make citizen’s arrests only when they witness a crime in progress and the perpetrator is caught red-handed.

A suspicious appearance and a chance to gain clout are not legal grounds for a citizen’s arrest.

The 30-year-old man who posted the video shot at Shin-Okubo Station told The Asahi Shimbun that he is a YouTuber determined to fight gropers and voyeurs.

Boasting more than 220,000 subscribers, he has posted at least 280 videos on the website since February.

He said he searches for suspicious people in train stations or on the streets, makes them apologize for some supposed crime, or even takes them to the police.

In some of the videos whose titles include “arrest” and “neutralization,” he gets physical with the subjects.

The video from Shin-Okubo Station, which is used by at least 40,000 passengers a day, was viewed more than 170,000 times, while it garnered over 36 million impressions after it was posted on X, formerly Twitter.

However, his mission has never provided any solid proof of criminal activity. One viewer said the YouTuber has no right to go around bothering people. Another expressed concerns that he was going out of control.

Actual crime fighters are not impressed by the videos.

An investigative source said the man at Shin-Okubo Station was released immediately after he was taken to the police box because there was no proof he committed any crime.

“We hardly ever arrest suspects based on such videos,” the source explained.

The YouTuber, citing his own filming experience, said he felt the man was possibly taking sneak photos or videos.

But he stopped short of providing evidence, and he acknowledged that he posted the video in hopes of gaining publicity.

He added that he doesn’t blur out the faces of his targets in about 10 percent of his videos.

The YouTuber receives ad revenue when his videos are viewed, and he also solicits paid subscribers.

“I want to increase the number of views and earn money,” he said, adding that he also aims to raise awareness about the current landscape of sex crimes.

An X account with about 16,000 followers uploaded a video in August showing the poster physically restraining a man, claiming he resold tickets for a concert of a popular idol group.

The man’s face was not blurred out, and the post gained at least 9.2 million impressions.

CONCERNS FOR PRIVACY, ASSAULT

A senior investigator at Tokyo’s Metropolitan Police Department frowned on the poster’s actions in the video.

“Because physical restraint is an act that restricts the rights of citizens, investigations must be conducted carefully based on victims’ accounts and footage of security cameras,” the investigator said.

Lawyer Yohei Shimizu, who is well-versed in internet issues, said that posting videos without blurring out faces could infringe upon privacy rights.

“Attention must also be paid to prevent social sanctions and unwarranted attacks (on those shown in the videos),” he said.

Takehiro Oya, a professor of legal philosophy at Keio University, said the citizen’s arrest provision in the Criminal Procedure Law doesn’t mean private citizens can exert authority on behalf of the police.

He added that excessive physical restraint could constitute a criminal assault.

As for exposing faces in video footage, the professor said excessive social sanctions should not be employed.

“Similar posts will continue to increase unless platformers set up a system to control extreme publicity stunts and anti-social content,” Oya said.

Google, which operates YouTube, told The Asahi Shimbun that the company forbids abusive actions, such as intimidation and doxxing.

The IT giant also explained that it has deleted some videos depicting citizen’s arrests after determining that they violated policies concerning harassment and online bullying.