In case you missed it: the man whose case sparked months of protest in Hong Kong has just been released.

Chan Tong-kai was arrested in Hong Kong after being accused of murdering his pregnant girlfriend in Taiwan last year. Hong Kong doesn’t have an extradition treaty with Taiwan, meaning Chan couldn’t be sent back to face trial.

Hong Kong wanted to change its extradition laws as a result, but also wanted to include China in the list of countries suspects could be sent to – which is what triggered widespread demonstrations by folks fearful of China’s reach into Hong Kong territory.

Much has been written about police use of hi-tech methods to curtail the protests, and of course it takes place against the backdrop of China’s long-standing Internet censorship regime and its recent aggressive push into facial recognition technology.

Demonstrators were filmed pulling down a “smart lamppost” which they feared contained a facial recognition camera. In fact, it reportedly held a Bluetooth beacon, a device which is usually used to send a one-way transmission to a phone allowing the handset to work out its location – a bit creepy, but nowhere near as pernicious as facial scanning tech.

Suspicion over government use of face recognition systems was stoked, however, by its decision to ban the wearing of masks. The administration claimed this was an emergency safety measure, but for a group already concerned about scanning technology, it looked like an attempt to make sure their faces were exposed. The more hi-tech the surveillance, the more low-tech some of the solutions: demonstrators hid behind umbrellas and reportedly placed cardboard boxes over cameras.

It’s far from clear what tech is being deployed and how, let alone under what legal regime. On the one hand, Hong Kong has some quite strict privacy laws, and its government claims it is not using facial recognition on government buildings’ CCTV cameras. The country’s police force, however, are legally able to use tactics like facial recognition to tackle crime, and have been far less forthcoming than their government colleagues about their use of hi-tech surveillance. Inevitably, much of the police work will be done in secret

As ever, the tech sword cuts both ways, and the protestors have embraced encrypted apps, notably Telegram, to organise meetings and share sensitive info. In June, the administrator of one of the largest Telegram groups, Ivan Ip, was arrested and charged with inciting others to cause a public nuisance. It’s unclear how they tracked him down, but it’s worth noting that for all its encrypted technology, Telegram is largely made up of open, public groups which anyone can join. Ivan Ip seems to have been running such a group it’s possible that there was enough public information available to identify him. The idea that Hong Kong law enforcement had somehow hacked Telegram to get his info seems far-fetched.

However, the very fact that the protestors are using secrecy-focused apps like Telegram, and not mass-publicity machines like Facebook and Twitter as they have in previous years, speaks volumes. The unsettling truth is that in some ways it doesn’t matter whether Hong Kong is using cutting edge computing to crack down on protests: the very suspicion that it is doing so could be enough to stifle dissent by driving campaigners into a plethora of different, secretive communications channels, hamstringing their ability to unite.

As Ivan Ip himself put it: “People are getting muted, as the regime wants.”