(CNN) -- Ai Weiwei's official probation period may have ended, but the internationally-renowned artist and political dissident is pessimistic about his pending tax evasion case and the rule of law in China.
"I feel very sad, very miserable, actually," he said in an interview Friday with CNN at his studio in Beijing.
Despite the relative freedom of having his travel ban reduced to leaving the country instead of the Chinese capital, Ai was not ready to celebrate.
"You always feel vulnerable and you are not protected by law," he said, adding that he has "no illusion ... any sort of change could be made."
Ai, 54, was denied access on Wednesday to the first court hearing in his tax evasion case, which he contends is baseless and politically-motivated. He said more than forty police cars and hundreds of officers surrounded his home. "You just cannot go, if you try, you cannot make it," he claimed the police told him. Public buses were also prevented from stopping in the area of the court," he added.
"They use the tax case to crush me but they don't want me to show up because...all facts can be revealed." Ai likened the court proceedings to a "very bad play" and said he was feeling "very discouraged" and "powerless."
"The outcome is very clear. The court works for the police; the tax bureau also works for the police; the police is becoming a superpower in China...And they decide everything because we have a policy: it's called 'maintain stability'...But what is stability? Is it stability of the nation? Or of the people? Or stability of the controller?"
The outspoken artist, blogger, documentary filmmaker, and architect was on his way to Hong Kong in April 2011 when he was taken into custody at Beijing's international airport and detained for 81 days amid a government crackdown on political activists. Ai's studio in Beijing was raided, and his wife and several employees were taken into custody for questioning. The government campaign was attributed to fears of a potential Arab-Spring-style uprising, following online calls for a "Jasmine Revolution."
Seven weeks after Ai was taken into custody, state news agency Xinhua reported that Beijing police said his company, Beijing Fake Cultural Development Ltd., evaded a "huge amount of taxes" and "intentionally destroyed accounting documents."
He was released on probation the following June and subjected to severe restrictions on his movements. Ai was forbidden to speak to the media or post on his Twitter account about his detainment. His phone was tapped, his e-mails were checked, and he had to report his appointments with other people to the police.
"I'm always followed by two or three cars and have police around," he said. "Even [when I'm] walking in the park, you see them taking photos behind the bushes and trying to videotape everything."
Ai said although he initially minimized his communications, he continued to post on his Twitter account. "I ask myself if I can really stop," he said. "I'm an artist. I have to have a real touch with reality...I have to express myself. I have to communicate. So what I did is really minimal...demanding for human rights and for freedom of expression."
In November, the authorities demanded he pay RMB 15 million (US$ 2.4 million) in back taxes and fines within two weeks. Tens of thousands of supporters donated more than US$ 1 million to help him pay the bill, some even throwing RMB100 notes folded into paper airplanes over the gate of his house. Ai used the donations to post a payment guarantee of the invoice in order to file an appeal against the charges.
Despite the lingering uncertainty over how the case will go, Ai said, "I don't think I can stay quiet. But also I don't know how long I am allowed to have some voice."
CNN's Eunice Yoon contributed to this report.