BANGKOK—Intensifying a crackdown on dissent in advance of a Communist Party Congress, Vietnam has charged a prominent American-educated human rights lawyer and at least two associates with the capital crime of subversion, the official press reported Wednesday.

The lawyer, Le Cong Dinh, 41, was arrested in June along with four other prodemocracy campaigners. All had at first faced the more common and less severe charge brought against dissidents of spreading antigovernment propaganda.

Two months later, a shaky video showed Dinh sitting in his shirtsleeves at a small, bare table and reading out a handwritten confession as his jailers shuffled around noisily off-camera.

“;I regret my wrong actions,”; Dinh said, looking down at the text. “;I wish the state to consider clemency for me.”;

That confession and similar ones by other dissidents are part of a crackdown that human rights groups say has included dozens of arrests and prison terms.

In October, nine people were sentenced to prison terms ranging from two to six years for hanging banners that called for multiparty democracy.

Diplomats and political analysts say the arrests are meant not only to punish but to set out the boundaries for discussion in advance of the next Communist Party Congress, set for early 2011.

“;It's a shot across the bow in advance of the congress to tell people to keep their heads down,”; said Carlyle B. Thayer, a specialist on Vietnam at the Australian Defense Force Academy in Canberra. “;Now is not the time for you to advocate political liberalization.”;

The arrests have drawn condemnation from Western governments and human rights groups, putting the Vietnamese government on the defensive.

On a visit to Slovakia a week ago, President Nguyen Minh Triet said Vietnam should not be subject to the standards of the West.

“;Laws of each country are different,”; he said. “;They are based on the different historical and geographical conditions and that is why it is impossible to implement the laws of one state in the other country.”;

Vietnam officially gave up Communist economics in 1986 with a policy called “;doi moi,”; or economic renovation, and it has been liberalizing its economy since then, joining the World Trade Organization in 2007.

But as Vietnam moves away from Communist orthodoxy in parallel with China, analysts said, there are people, particularly among a lower-ranking younger generation, who believe the country is stable and prosperous enough now to loosen its political system.

As factions struggle over the wording and substance of the policies that will emerge from the next party congress, the voices for liberalization are pushing to be heard both within Vietnam and among an active anti-Communist diaspora that is making vigorous use of the Internet.

The crackdown has sought to contain those voices, introducing tighter limits on press freedom and on Internet discussion sites including political blogs. Access to Facebook has recently been restricted.

At a meeting of World Bank donor nations earlier this month, the U.S. ambassador to Vietnam, Michael W. Michalak, spoke of a “;shrinking of the space for honest, reliable information,”; Agence France-Presse reported.

The charges against Dinh illustrate a concern, periodically repeated in the official press, over what is seen as a destabilizing influence of contacts with the West—“;peaceful evolution,”; in the Chinese and Vietnamese term. The warnings point to the collapse of the Soviet Union in 1989 and to peaceful uprisings that brought down governments in places like Ukraine and Georgia.

Among the accusations against Dinh was that in March he had attended a three-day training course in Thailand, sponsored by an overseas Vietnamese political group, at which two Serbians made presentations about methods of peaceful change.

According to a report Wednesday in the newspaper Thanh Nien, Dinh and his associates “;colluded with Vietnamese reactionary groups and hostile forces in exile”; to form a reactionary political organization “;aimed at overthrowing the people's government through nonviolent means.”;

Dinh and his colleagues are expected to go on trial soon under Article 79 of the Penal Code, “;carrying out activities aimed at overthrowing the people's administration.”;

Dinh, who studied law at Tulane University in New Orleans for two years on a Fulbright scholarship, has often met with diplomats and other foreigners.

He has served as vice chairman of the Ho Chi Minh City bar association and practiced on behalf of the government several years ago when he successfully represented Vietnamese catfish farmers in a dispute with American fishermen.

More recently his activities have taken on a political tone, and he has published prodemocracy essays on the Internet and defended human rights lawyers accused of anti-government propaganda. Among other things, according to the charges against him, Dinh used his platform as a defense lawyer to speak out about human rights.

In a 2007 court appearance, he reportedly said: “;Talking about democracy and human rights cannot be seen as anti-government unless the government itself is against democracy.”;