I was a news reporter for eight years before I quit my job. For three of those years I sat daily in the gallery of the Intermediate People's Court in Guangzhou, listening to cases. A criminal trial might last for two or three hours, with the verdict and sentence announced in a 15-minute hearing several months later. During that time, I watched a big-shot drug dealer do everything in his power to protect his wife. I witnessed a pair of lovers tearing each other to pieces in a venomous bid to get themselves off the hook. And I once saw an African guy break down in huge howls, then whimpering sobs, on getting 10 years for trying to smuggle a few hundred dirty movies out of the country. His interpreter had to tell him a few times before he took it in.

I don't know why the air conditioning was turned up so high in that building. The women journalists used to bring long-sleeved shirts to wear. The families of the accused and the victims alike would sit, pale as ghosts, in those big empty corridors. I never had the heart to interview them, so my reports lacked color. I have many more fragmented memories of this kind. But more than anything, I will always remember the icy chill that hung around the place. I never thought I'd come to think this years later, but at least that cold existed tangibly in the real world. And at least it was witnessed by those Chinese journalists, even though they couldn't see what was wrong with it. I was about to learn a whole lot more about that ice-cold world, which is never spoken about inside the Great Firewall.

I covered the annual parliamentary sessions in Beijing five times in all. I was there in 2008 when Premier Wen Jiabao gave his press conference. We'd joined the line outside the Great Hall of the People at 6.00 a.m., but I and my colleagues were still only able to grab seats at the back, where Wen's voice seemed to reach us from a very great distance. I remember the last question. The premier said he wanted to give a French journalist a chance to ask something, but then a Reuters journalist stood up and said there was someone called Hu Jia currently standing trial on charges of "incitement to subversion." That was the first time I heard his name. A month later, Hu Jia was sentenced to three-and-a-half years in jail.

While Hu Jia was in prison, I got to know his wife and daughter, who lived just across the Yunhe River from me in Tongzhou. They often came round to my place, where the little girl had her first Magnum ice-cream. She also liked to eat my chicken wings, which I would glaze with Coca-Cola or honey. She sat there and taught herself to crack open melon seeds while the grown-ups were talking. One year, I bought her a pretty white, floaty dress for Children's Day, but even the smallest size was too long for her. Her mother hung it up in the closet, and the little girl kept asking every five minutes: "Mommy, Mommy! I want to see the wedding dress that Auntie gave me!"

To begin with, she thought her father had gone away to study. But gradually she began to have doubts, and no matter how hard the adults tried, we couldn't create a safe world for her, peopled only by the likes of McDull and Garfield. She grew up too fast. I don't know when she first learned the meaning of the words "state security police", or when she first started using them, but it was the first rent in the veil we had tried to cast over such things in the real world. After that, we couldn't stop her from seeing them. She's in Hong Kong now. I'm happy that when she opens her window, it's the salty tang of Victoria Harbour that greets her, and not a bunch of guys in dark clothes sitting in black sedan cars parked downstairs; not the guobao.

Even though I had seen them too, it took me a while to accept that They existed, and that They weren't just something out of the convoluted plot of an Eastern European or Soviet-era movie. My memories of Them, what they actually looked like, will always be hazy. In my mind, they are just screws in the state machine, still dizzy from being screwed in too fast and too tight. They no longer know which way is up. And after they do this kind of work and live this kind of life for a while, they lose all sense of right and wrong.

In 2009, a few friends came over to our place to spend Christmas Eve with us. One of them got a ride to the foot of the building from a couple of state security police. We used to jokingly call this "special transportation arrangements". It was about 10 degrees below freezing in Beijing that night, and there was a strong wind blowing, so we invited the cops inside as well. We had an enclosed balcony area with an electric heater, that was fairly warm. We thought maybe a fake fire would kindle some genuine warmth in the hearts of the screws, one of whom might even loosen up a bit. When midnight struck, we all hugged each other. I gave a brief hug to one of the state security cops, a giant of a man, and it seemed to me as if this screwed-up guy suddenly became human in that moment of bodily contact. Of course I have no idea how he felt about it. Maybe he was just going through the motions.

Another time, they came to search our home while my parents were visiting Beijing. My mother asked one of them shyly in her Sichuan dialect: "Would you like a cup of tea?" He declined to drink our tea, though it was hard for him to maintain his uptight attitude when this kind old lady was offering it. But such moments pass quickly. And then They are still Them, just doing their job, and we are still us, the dissidents, the people who don't exist, according to a foreign ministry spokesperson.

I went to see Les Miserables in New York a while ago. By the end, the movie theater was full of the sounds of sobbing and applause. What stayed with me was Javert, who, faced with the realization that his beloved law was inadequate when it came to decoding events in the real world, could only choose death. I would love to take Them to see this movie. I have never had very high hopes of human nature, but I would like to see them unwind just a bit, and then maybe a bit more. Sometimes you don't need a revolution like the one in Les Miserables to turn the world upside down; all you need is for a single screw to come loose.

Lately, I've been doing a bit of reading, and I have been most impressed by Hannah Arendt's Eichmann in Jerusalem, in which she talks about the banality of evil, an increasingly familiar concept for a lot of people. She sums it up best in the following lines: "The essence of totalitarian government, and perhaps the nature of every bureaucracy, is to make functionaries and mere cogs in the administrative machinery out of men, and thus to dehumanize them." Another is, "in politics, obedience and support are the same".

They published a Chinese translation of Jonathan Littell's The Kindly Ones a couple of years ago, under the title Nemesis. The novel is a 700-page meditation on the above quotations from Arendt. Its narrator muses: "The machinery of the state is made of [a] ... crumbling agglomeration of sand ... It exists because everyone – even down to the last minute, its victims – agrees that it must exist. Without the Hösses, the Eichmanns, the Golglidzes, the Vyshinskys ... a Stalin or a Hitler is nothing but a wineskin bloated with hatred and impotent terror."

Just as there was an Oskar Schindler among the Germans, so there must be a loose screw among Them too, hiding. And just when the sprawling machinery of the state seems to be running well, that screw will fall out, stretch itself on waking, and shine its own small ray of light into the dark world around it.