Lockdown Voices: Big-data Glitches, Yellow Health-codes, and “Spatial-temporal Companions”

As the third year of the COVID-19 pandemic approaches, China continues to adhere to a stringent “zero-COVID” policy, long after many other nations (including Australia, Singapore, and New Zealand) have abandoned their total-containment policies due to the spread of the delta variant and a shift toward long-term coexistence measures. Weary of constant lockdowns, mass testing, forced quarantines and lost wages, Chinese netizens from all walks of life have sought to tell their stories, offer suggestions or weigh in on the debate surrounding COVID policy, only to have their voices censored online, or to suffer retaliation for speaking out.

CDT has endeavored to amplify these “lockdown voices” in a three-part series. Part one (Lockdown Voices: Ruili and Yili Speak) focuses on the tremendous toll that China’s pandemic containment and control measures have exacted on residents of border towns such as Ruili and Yili, and the ways in which their pleas for help were met with empathy by Chinese netizens and censorship by local and national government officials. Part two (Lockdown Voices: Chinese Doctors Urge More Humane COVID Policies) highlights groups and individuals who have contributed to the ongoing debate about the best long-term policy for managing the novel coronavirus. In part three (Lockdown Voices: Big-data Glitches, Yellow Health-codes, and “Spatial-temporal Companions”), we turn our attention to the ways in which the ubiquitous red, yellow and green phone-app health codes have changed people’s lives, circumscribing their freedom of movement, access to resources, opportunity to work, and ability to interact with others.

For a brief introduction to Chinese contact tracing apps, the Forbes Technology Council provides an informative summary of some specifics:

China was the first country to introduce a contact tracing app into the lives of its citizens. The app Health Code was developed by the giants of the Chinese Internet: Alibaba and Tencent. The app assigns a green, yellow or red code to each citizen, which indicates their risk of having been exposed to the virus. A green code grants freedom, a yellow one means you’ll probably have to stay home for a couple of days, and red means a two-week quarantine. The criteria for color are unclear: neither the Chinese government nor the developers have revealed how the algorithm works. This, of course, has caused nationwide anxiety, scandals and distrust.

While the app is not technically mandatory, it’s almost impossible to survive in China without it: Subways, malls and other public spaces require the app ― and the green code. The installation is easy: Health Code was integrated into the widely popular Alipay (online payment platform) and WeСhat (social media platform). In most cases, users didn’t have to download anything new: just provide their name, phone number, national ID number, home address, health records and travel history. Once this information is out there, it’s not private anymore: A New York Times report revealed that the app shares the information with the police.

This, however, isn’t even the only concern regarding Health Code[s]. Despite the overwhelming adoption of the app (something other countries have been struggling with), it’s impossible to assess its efficacy. There is no information on the technology behind it ― we don’t know anything about the quality of data and the hypothesis behind the algorithm. And, because the app doesn’t detect actual occurrences of close contact, there is no way to prove or disprove that it works to stop the spread of the virus. [Source]

There are concerns, bolstered by personal accounts, that the health code app could be used selectively to impede the movement of or arbitrarily quarantine activists, journalists, civil rights attorneys, and others targeted by Chinese public security. CDT Chinese recently published an account by Chengdu-based attorney Liu Jianyong in which he describes how his health code turned abruptly from green to red as he was passing through Xi’an en route to a trial in the city of Shangluo, Shaanxi Province. Liu was mystified: he was fully vaccinated, had had no direct contact with any infected individuals, his health code had remained green during his entire time in Chengdu, and he had completed three nucleic acid tests, all negative, within the previous 48 hours. When local pandemic prevention and control personnel in Xi’an informed him that he would have to miss his court date and enter quarantine in Shangluo, and that pandemic prevention and control personnel from Shangluo were already on their way to transport him there, Liu put his foot down. As an attorney well apprised of his legal rights, Liu informed the pandemic control staff that he refused to consent to quarantine, and demanded to see all documentation pertaining to the quarantine order. Although he did end up missing the trial, Liu Jianyong was eventually allowed to proceed on his way unimpeded. His exchange with the Shangluo pandemic control personnel, translated in part below, is telling:

Liu: What is the legal basis for putting me in quarantine?

Pandemic Prevention and Control Personnel (P): The People’s Government of Shaanxi Province issued an order that says cases like yours must be forcibly quarantined.

Liu: I don’t consent to the quarantine. If I can’t go to Shangluo Intermediate People’s Court, I’ll just return to Chengdu.

P: According to the regulations, you can’t return to Chengdu. You must quarantine in Shangluo.

Liu: My household registration, regular place of residence, and place of work are not located in Shangluo, and I have no legal connection with Shangluo. I just have to be there for a court case tomorrow, but I’ve never even been to Shangluo before. Why would I quarantine there and not in Xi’an? I don’t consent to quarantine. What is the basis for your quarantine?

P: The Shaanxi Provincial Government issued the order. We’re just following regulations.

Liu: What order? Please show me this document. I want to see this document.

P: We don’t have the document on hand. We’re just carrying out our bosses’ orders.

Liu: The document is not a state secret. You may not have it, but your boss certainly does. Have your boss bring it to me. If your boss doesn’t have it, then have your boss’s boss bring it over. Whoever has it, bring it to me. I have the right to know.

P: You don’t have to give us a hard time. We’re just doing our job.

Liu: I’m not giving you a hard time, nor am I targeting you. I understand that you are just carrying out orders, and that your work is dangerous and difficult. But this document concerns my vital interests, and if I am to be taken, for some vague reason, to a place where my personal freedom of movement will be restricted for 14 days, I demand that I be allowed to avail myself of all avenues of redress. Since the Shaanxi Provincial People’s Government has issued this order that you are carrying out, this counts as an administrative action, and I, as the object of this administrative action, am asking you to produce this document, or to produce the law or regulation that forms the legal basis for this action.

P: But I’ve already signed the paperwork, and reported your situation to my superiors. The car will be here any minute. How can you not go?

Liu: You haven’t received my consent, so the paperwork isn’t legally valid. I don’t agree to be forcibly quarantined, and I won’t sign. Who do you work for?

P: The public security bureau.

Liu: Which specific public security bureau? Municipal or district? What is your name and badge number?

P: The Shangluo Municipal Public Security Bureau.

Liu: I’m going to file a complaint against the Shaanxi Provincial Government alleging that this order exceeds the scope of forced quarantine over the population: it’s excessive vigilance, rather than precise, scientific prevention and control, and it’s inhumane. Also, this administrative action of yours violates the principle of reasonable, proportional administrative legal action. I want to reiterate that I do not consent to compulsory quarantine.

P: I’ll have to report this to my superiors.

And so the officer called his boss, spoke for a while, hung up and said to me, “You should hurry up and buy a high-speed train ticket back to Chengdu.” [Chinese]

A number of Chinese cities have recently expanded the use of yellow health-app codes based on “spatial-temporal proximity” (时空伴随), a designation determined by the locations of individuals’ cell phone signals. The rather vague and confusing term has now become ubiquitous, and generated a great deal of online discussion, dissection, criticism, and mockery. A recent China Digital Space post from outside contributor “Tulip” explored “spatial-temporal proximity” and examined how it affects people’s lives:

What is “spatial-temporal proximity”?

The China National Health Commission’s “Guidelines for the Determination and Management of Close Contacts” defines a “close contact” as a family member living in a shared space with an infected individual, or any person who has had close contact with an infected individual in a shared space.

People used to talk about their phone app health codes changing color after close contact [with an infected person], but in this era of “spatial-temporal proximity,” health codes can turn yellow even without any close physical contact. Health authorities in Chengdu, Chongqing, Changsha, Jiayuguan, Zhengzhou, and other places have started defining very large groups of people as “spatial-temporal companions.”

[…] According to a definition released by CCTV News, if an infected individual has visited a certain location within the past 14 days and your trajectory has intersected with them during those 14 days—no matter whether you brushed past them physically or whether your cell phone signals simply intersected—you may be classified as a “spatial-temporal companion” of the infected individual.

On November 3, 2021, police in Chengdu used the trajectory of a recently-infected individual to identify 82,000 “spatial-temporal companions,” forcing the residents of several local communities to take overnight nucleic acid tests. 

[…] This policy has had a major impact on the work and lives of Chengdu residents, and the internet has been inundated with posts complaining about it.

One person said, “With the way things are going in Chengdu, it won’t be long before everyone in Chengdu has a yellow code. It’s because people move around too fast: the grid is a dead thing, but people are alive.”

An anonymous post on Zhihu read: “You can be sitting at home, and a yellow code pops up out of nowhere. I had to take three nucleic acid tests in three days. And because my code had turned yellow, my daughter wasn’t allowed to go to school until the whole family had two negative nucleic acid tests within a space of three days. Ours isn’t a special case: on the night of the 5th, our whole neighborhood had to take nucleic acid tests because everyone’s codes had gone yellow.”

In an article titled “Overzealous Pandemic Controls Aren’t Just Arbitrary, They’re Idiotic,” published by China Digital Times, Xiang Dongliang—the author of the WeChat account 基本常识 [“Basic Common Sense”]—lists specific examples of bizarre pandemic prevention measures from around the country. One example is the health codes of every single resident of the city of Heihe, in Heilongjiang Province, turning yellow. [Chinese]

The vast expansion of yellow health codes based on cell phone signals and large spatial grids has triggered legitimate concerns about quarantine overreach, personal data privacy, and the limitations of public policy based on Big Data. CDT recently translated “What Happened When My Health Code Turned Yellow,” a post from a WeChat user in Xi’an who agonized about whether to risk exposing himself to the virus by standing in a crowded line for PCR testing after his health code turned inexplicably yellow after a trip to Tibet:

When compliance becomes a collective choice, when it affects all aspects of your life, and non-compliance introduces an immense amount of real, practical challenges, the dynamic becomes one of great power disparity, like trying to prop up a mountain with a twig.

[…] I’m a living, breathing human, after all. I need to eat and drink. I need to see my family and friends, go to the movies, go to the book store…and no one would let me in. I’d have a breakdown. I just can’t imagine how a normal, healthy individual could be labeled a threat by “big data” for nothing more than living in an area that a COVID-positive person once passed through. It’s like the plot from a sci-fi film I saw years ago, now becoming my reality. [Source]

An even stranger incident occurred when a man living in Xi’an returned from an overnight trip to the nearby city of Yuncheng, a low-risk area, only to discover that his health code had turned yellow and his travel passport app was insisting that he had recently traveled to the Philippines, which he clearly had not. What followed was an absurd, Kafkaesque tale of being shunted from one government agency to the next as he tried to correct this Big Data-driven mistake. CDT Chinese has re-published his post 《我被菲律宾了,我的行程卡变黄了》(“I’ve Been Philippined: My Travel Passport App Has Turned Yellow”), and a partial translation appears here:

However, many places have now adopted a simple one-size-fits-all approach to pandemic enforcement, without taking into consideration the possibility of mistakes or specific individual circumstances. In over to avoid taking personal responsibility, they prefer to double down on enforcement, take rapid and efficient control of the populace, and deal with problems quickly and resolutely; but the moment an individual makes a specific appeal for assistance, it devolves into a farce of government departments passing the buck, shifting the blame, and behaving with aggravating inefficiency. What I experienced was a very minor inconvenience—hardly worth mentioning in comparison to the many people who have suffered 14-day quarantines, business closures, and all manner of delays and losses due to the effects of the pandemic—but I think that some of the problems it revealed are worth thinking about.

[…] The measure of true safety is not simply avoiding infection or maintaining public order, but also being able to travel normally, to express our opinions with reasonable freedom, and to get problems solved in a timely and effective manner. With the pandemic still raging and a state of emergency now the norm, having to constantly worry about being yellow-coded or red-coded, or being constantly anxious that your most minor word of protest will be distorted or misconstrued—that in itself is a sense of insecurity, a feeling of being unsafe. [Chinese]


The travel passport app of the man from Xi’an appears yellow, and mistakenly shows him having traveled to the Philippines.

The use of mobile phone health-app codes, cell phone signals, vast grids, and mass testing has changed the way people conceive of social contact and social relationships, and has expanded surveillance into nearly every corner of Chinese citizens’ public and private lives. Veteran blogger Wei Zhou considers these and other issues in The Risks of Spatial-temporal Proximity,” a recent essay published by CDT Chinese and partially translated here: 

“Spatial-temporal proximity” sounds like something out of science fiction, but plainly put, it is a form of spatial-temporal grid supervision: by mapping out the trajectory of a patient diagnosed with COVID and tracking the places and times at which he/she appeared, anyone within an 800 x 800 meter range of the patient’s cell phone signal (based on the nearest cell phone base station) will be designated as a potentially infected subject, unless this designation is removed after testing and quarantine. 

Diagram showing an infected individual in blue, a “spatial-temporal companion” in yellow, a cell phone base station in the center, and an 800 x 800 meter grid.

You may not know this individual at all, nor even see him/her, but by the mere coincidence of appearing in the vicinity of that spatial-temporal point, you and he/she have now become “spatial-temporal companions.”

A few days ago, I saw a story online about a female passenger who tried to board the number 47 bus at Chengwen Overpass Station in Chengdu. When she displayed her health app code, it was red, and she had no idea at what point it had turned red. After that, nobody on the bus could get off or change buses—they just had to wait for pandemic personnel to arrive and sort it out. They had all become “spatial-temporal companions.”

In China’s “relationship-based society,” “spatial-temporal companionship” seems to have created a new relationship outside of the traditional Confucian “Five Cardinal Relationships.” We might dub this the “Sixth Cardinal Relationship”: you are inextricably bound to this relationship simply because of your inadvertent association with others.

[…] What’s worse is that the technical aspects of the health code seem to vary from place to place. I heard from a friend that he went to Putian last month with some folks from Zhejiang. A few days later, there was an outbreak in that area: his health code, and those of his colleagues from Fujian, didn’t change color, but the codes of the Zhejiang folks turned red, and they had to be quarantined.

This is not an isolated case. A friend from Hengyang in Hunan Province told me about a company reunion that took place during this summer’s outbreak in Zhangjiajie. After everyone went back home, their health codes changed color, but two of their former colleagues’ codes stayed green. They had been together the whole time, participating in the same activities in the exact same places, so why would there be such a difference in their codes? After thinking it over, my friend decided there was only one rational explanation: the two with green codes had China Unicom SIM cards, while all the others had either China Mobile or China Telecom. There was one person in Changsha who had two SIM cards: one showed a green code, and the other, a yellow code.

[…] The real problem is not the crude application of technology, but why we pursue these goals in the first place, and why prevention and control mechanisms don’t kick in until the situation is beyond tracing and beyond control.

Trying to control the overall “environment” rather than focusing on individual autonomy inevitably results in the situation we see now: the daily sense of fear, on the one hand, and the carelessness of individuals, on the other. As long as people feel that the “environment” is safe, they will continue to gather together at any opportunity, as if they are counting on the presence of someone or something beyond the individual to keep the situation in hand, so that they as individuals don’t need to take the initiative or expend any additional effort.

One thing is now clear: even if the pandemic passes, our lives will never be the same—we will never go back to the way we were before the pandemic. As for today’s problems, we can only hope for greater technical accuracy and fewer uninfected people being caught up in quarantines, as we ask who should bear the risks, what level of risk is acceptable, and ultimately, how many of our personal rights we will have to concede in order to feel safe. [Chinese]

Attempts to resume quarantine-free cross-border travel between mainland China and Hong Kong have also been complicated by the stark differences in the health code apps used by each. The recently detected B.1.1.529 strain of SARS-CoV-2, now known as the Omicron variant, may put efforts to create a mainland/Hong Kong “travel bubble” on hold for some time, but concerns about intrusive surveillance measures and personal data privacy persist. Bloomberg reported on the differences between Hong Kong’s “passive tracing” app and the mainland’s much more intrusive app:

In mainland China, a health code that dictates where citizens can travel has been mandatory since the pandemic hit. Hong Kong’s contact tracing app doesn’t even know a person’s name.

That gap in surveillance has become a major sticking point in protracted talks about restarting quarantine-free cross-border travel, which could happen in a limited capacity as soon as December, the South China Morning Post reported late Thursday. 

Earlier this month, Hong Kong Chief Executive Carrie Lam told a local news outlet that she had no plans to add a tracking function to the city’s LeaveHomeSafe app. But she also warned that residents would need to download their records if they wanted easier access to the mainland. 

[…] “The main concern is that many Hong Kong people are quite concerned about the privacy issues,” Lam Ching-choi, a member of the government’s advisory Executive Council, said in an interview. 

[…] “To what extent the Hong Kong government could adopt an authoritarian approach on this key public health issue would serve as an indicator on how far authorities would go to convert Hong Kong to another Chinese city,” said Xiaomeng Lu, director of Eurasia Group’s geo-technology practice. [Source]


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