The Hong Kong police broke into thousands of mobile phones belonging to detainees and suspects between June and November last year, the city’s secretary for security recently revealed. But key questions were left unanswered: How did the police manage this? What kind of search warrant granted them this access? Were those whose devices were searched served with warrants? Did they even know that their devices had been searched?

Now, thanks to a judicial review application filed yesterday (Jan. 13) challenging the police decision to search many devices, we can begin to answer some of those questions.

A 22-year-old photographer named Lee Wing Ho applied for the judicial review. Lee was arrested in August (link in Chinese) in the Mong Kok neighborhood where a protest was underway. He was charged with unlawful assembly. Lee’s possessions, including a mobile phone, several memory cards, and a SIM card were confiscated by the police. When he was being prosecuted for unlawful assembly, Lee learned that the police had obtained two warrants to search his mobile phone and other electronic devices.

But there was something not quite right about the warrants. First, Lee wasn’t served with them. Second, the warrants authorized the police to search the 22nd floor of police headquarters. Why would the police seek a warrant to search their own premises?

The warrants gave police the right to search the digital content on 57 devices located on the 22nd floor of police headquarters, according to the judicial review application. But Lee didn’t have 57 devices or anywhere near that number on him when he was arrested. Lawyers representing Lee therefore inferred that the police “having arrested and confiscated a large number of smartphones and electronic devices from a number of suspects on different occasions and having brought them to the 22/f of Police Headquarters” sought two warrants “to access all of them without conditions or limitations.”

Lee’s application for judicial review said that “a search warrant obtained by the police to access objects inside a police building is an abuse of process, an artifice.” He also noted that the warrants did not specify the identities of the suspects, nor where and when the alleged offence took place. The warrants, the applicant argued, are therefore unlawful.

“Indeed, there is no way of knowing whether the electronic devices came from persons suspected of unlawful assembly at all,” the application continues. “They could just have been electronic devices, seized from any arrested person, and now transferred to and kept in Police Headquarters.”

The allegations have serious implications for citizens’ right to privacy, which is enshrined in Hong Kong’s Basic Law, the city’s mini-constitution that is meant to set it apart from mainland China’s legal system.

It’s unclear if the police used similarly vague and sweeping warrants to search the thousands of other phones that Hong Kong secretary of security has said were accessed. If so, there is the possibility that many of the nearly 7,000 people arrested during the months of protests that started in June may have had their phones and devices searched without their knowledge. Hong Kong police has not responded to Quartz’s requests for comment.

Activist Joshua Wong has also sounded the alarm, noting that though he never gave police his phone password after being arrested in August, prosecutors last month presented him with a list of Telegram and WhatsApp chat messages from his iPhone. As of Jan. 15, the police have still not returned his phone.

Charges against Lee have since been dropped, but his phone has yet to be returned, according to the judicial review application. For all we know, police could still be poring over the contents of his phone.