A visitor to Bao Tong's apartment - with armed guards in the parking lot and another checking the identifications of guests - might think they're about to meet one of China's most dangerous criminals, rather than a former top official in the Communist Party.
But to the men who rule this country, Mr. Tong is both, which makes him a bigger threat than the sprightly 76-year-old looks like he could be. To them, Mr. Tong is the party official who, along with his boss, former Communist Party secretary Zhao Ziyang, almost brought down the whole system 20 years ago by daring to agree with the students demanding change in Tiananmen Square.
Mr. Tong is still campaigning for change, criticizing the government when he gets the chance, and helping pen a recent manifesto for change that was quickly banned.
"There are four buildings in this compound, and only this one has this much security," Mr. Tong says with a resigned smile as he receives a rare foreign guest. "And only visitors to this apartment need to register."
Mr. Tong's main "crime" was a speech he wrote 20 years ago today. On the morning of May 4, 1989, Mr. Zhao asked him to write remarks that he would deliver a few hours later in an indirect address to the crowds of students who had been protesting for three weeks in Beijing and other cities.
As he furiously scribbled speaking notes in the back of a car as it moved through the streets of the capital, Mr. Bao, then the director of the Office of Political Reform and policy secretary to Mr. Zhao, knew his country's fate hung in the balance. He dared believe he was helping to change China, setting it on a more open and democratic course.
"I was very excited. I thought that the party was bringing its opinions into the same line as the people. It was historic progress," Mr. Bao remembered in a recent interview.
The instructions Mr. Zhao gave him were as delicate as they were monumental: a speech making it clear there were factions in the government that sympathized with the students calling for more freedoms and an end to official corruption.
The speech, delivered to delegates of the Asian Development Bank meeting in Beijing that afternoon, criticized China's "flawed legal system" and "our lack of democratic supervision as well as our lack of openness and transparency." These were historic words that caused an eruption of joy among the nervous and weary protesters on Tiananmen Square.
If the reformers had won out, the May 4 speech might be celebrated today as the moment China's one-party state started to dissolve, as other such regimes fell apart in Eastern Europe that same year. Instead, it is a speech that few young Chinese have heard of and no one is allowed to publicly discuss.
The speech evenly split the Chinese leadership, eventually placing Mr. Zhao in conflict with the country's senior leader, Deng Xiaoping, who Mr. Bao says was behind the eventual decision to declare martial law and use tanks and soldiers to break up the protests on Tiananmen on June 4, 1989. Hundreds of people, perhaps thousands, were killed in the bloody crackdown.
In the aftermath, Mr. Zhao was purged from the leadership, and lived under house arrest until his death in 2005. Mr. Bao spent seven years in the maximum-security Qincheng Prison for "revealing state secrets and counter-revolutionary propagandizing." He was the only senior Communist Party official to be prosecuted in connection with the events of 1989.
Since his release, he has also been under effective house arrest, trailed whenever he goes and only allowed visitors his guards screen.
During the rare and lengthy interview inside the apartment he was assigned in west Beijing, he spoke out again against the Tiananmen massacre and the system that persists today after so nearly crumbling in those dramatic days.
Mr. Bao believes things were very close to going the other way 20 years ago. He said that Mr. Deng initially expressed support for Mr. Zhao's speech, and stood against military action even as late as mid-May, only to suddenly reverse himself after an indecisive session of the Standing Committee of the Politburo on how to deal with the crisis.
"The students were very close [to succeeding] They were just one step away," Mr. Bao sighed, staring out the window at a Beijing skyline that has become dramatically more modern and crowded in the intervening two decades.
"One sentence from Deng Xiaoping was worth 1,000 sentences from others. I don't know what changed Deng Xiaoping's mind, but this change of mind caused all the [political]stagnation and backwardness in China over the past 20 years."
Mr. Deng made his opinions clear at a May 17 meeting of the senior leadership, and later that night Mr. Zhao asked Mr. Bao to draft his resignation letter. Two days later, Mr. Zhao made a stunning appearance on Tiananmen Square. "Students, we came too late. We are sorry," he told them through a bullhorn. He begged the demonstrators to end the hunger strike and to "think carefully about the future."
A state of emergency was declared the next day and soldiers and tanks began moving into Beijing. On May 28, just days before the army opened fire on the demonstrators in the square, Mr. Bao was arrested and jailed.
Since his release, Mr. Bao has continued to criticize the country's leaders even while under house arrest. The apartment he shares with his wife is spartan, the walls bare save an oversized family portrait with his wife, children and grandchildren that hangs above the television. A photo of a white-haired Mr. Zhao taken well after he left office sits atop a bookcase.
He acknowledges that the country has made astonishing economic progress in the past two decades, but Mr. Bao says China still suffers under "50 per cent of Mao's economic system, and 100 per cent of Mao's political system."
His movements are restricted, and Chinese media are forbidden from interviewing him, but Mr. Bao still manages to make waves. He was one of the key drafters of Charter 08, a manifesto released late last year that called for democracy and freedom of expression in China.
The government's firm response - all discussion of the Charter has been banned, and Mr. Bao's close friend Liu Xiaobo was jailed for his role in writing and circulating the document - has proven that Mr. Bao's ideas still have the power to scare the government. Some 8,000 people have signed their names to the charter since it was drafted in December.
Mr. Bao is frustrated at how the Chinese government has managed to suppress nearly all domestic discussion of what happened here 20 years, and that many foreign governments have chosen to forget in favour of building lucrative trade relationships with Beijing.
"I think this is proof of the efficiency of the government's policy. They are very successful at brainwashing. Young people below 20 know nothing about [Tiananmen Square] Even 30 to 40 year olds may not know exactly what happened because they were teens and schoolchildren at the time," he said.
"But I believe that as long as society is unfair, as long as there is inequality, people will chase freedom and democracy."