Traitors & Heroes A Lawyer’s Memoir<i> by Martin Garbus (Atheneum: $19.95; 352 pp.)</i>

In April, 1974, the Chilean junta of Gen. Augusto Pinochet announced that it would convene its own self-styled “Nuremberg” trials--treason prosecutions of 65 high-ranking army officers and two civilian supporters of deposed President Salvador Allende. In a carefully orchestrated campaign to clean up its international image, the junta planted stories in the nation’s newly censored press promising that the proceedings would be open to the public and conform to accepted norms of due process.

The trial, however, proved to be a mockery of both procedural and substantive justice. Avoiding the spotlight of the civilian law courts, the junta staged the hearings at the Air Force Academy on the outskirts of Santiago. The accused, who were charged largely with making pro-Allende speeches, had been held in pretrial detention for seven months while the junta suspended the writ of habeas corpus . Sixty of the defendants were convicted on the basis of coerced confessions and perjured testimony. Three who renounced their co-defendants were acquitted. The other four disappeared before the trials began. No appeals were permitted.

Were it not for a handful of American and European attorneys who submitted to body searches and myriad bureaucratic ruses to bear witness to the travesty, the world might never have learned the truth about the trials. Among those in attendance was New York City trial lawyer Martin Garbus. In “Traitors and Heroes,” Garbus has given us a superb memoir of his life’s work as a human rights activist.

Garbus’ travels have taken him not only to Chile but to South Africa, where he observed the treason trials of the acclaimed poet Breyten Breytenbach and 10 leaders of the African National Congress in 1977. The same year, he spent two weeks in the Soviet Union advising dissidents Andrei Sakharov and Anatoly (Natan) Sharansky in their legal wrangles with the Brezhnev regime. Garbus offers a moving and rare inside glimpse at the legal systems of all three nations.

But “Traitors and Heroes” is much more than an engaging personal saga. It is also a thoughtful reflection on the nature and evolution of the high crime of treason. As Garbus reports, contemporary notions of treason date back to the reign of England’s Edward III, when Parliament, in an attempt to limit the unbridled discretion of the Crown, enacted a statute defining treason as “compassing” or “imagining the death of the King, defiling the King’s wife, levying war against the King, adhering to his enemies” and sundry other misadventures.

In the modern era, treason statutes have become more abstract and depersonalized, with attacks upon the nation, rather than specific rulers, constituting the gravamen of the offense. Treason prosecutions have typically fallen into two broad categories: those directed against individuals accused of committing acts of violence against their governments and those directed against individuals accused of advocating or expressing subversive ideas.

It is with the latter that Garbus and the human rights community are primarily concerned. As in the Breytenbach case, individuals charged with subversive speech have frequently committed no overt acts to bring down the existing order. Far from being regarded as criminals, they are often viewed as heroes by significant constituencies.

Garbus has spent his career not merely observing the plight of these heroes but actively coming to their aid. It was Garbus and his wife who smuggled the famous letter from Sakharov to Jimmy Carter, exposing the predicament of political prisoners in Brezhnev’s Soviet Union and eliciting the first major pronouncement of the Carter Administration in support of human rights.

Similarly, on his return from South Africa, Garbus authored a series of influential news articles on the legal abuses of apartheid. The South African government retaliated by filing an ethics complaint against him with the New York State Bar. It took Garbus five years to persuade the Bar to drop the ensuing investigation.

In Chile, however, Garbus attained near-hero status himself. After filing a petition on behalf of the “Nuremberg” defendants, he was invited to meet in chambers with the chief justice of the Chilean Supreme Court. In an angry confrontation, the judge argued, as expected, that the trials complied fully with his country’s democratic traditions. What Garbus did not expect was the judge’s intimate knowledge of American legal history and, in particular, the political prosecutions of such left wing figures as Eugene Debs, the Rosenbergs and Alger Hiss. Debs and the others, the Chilean claimed, were traitors, the same as those brought to trial by Pinochet.

It would be easy to dismiss the Chilean jurist’s remarks as the exaggerations of an ideologue, but to his credit, Garbus does not.

In the book’s final section, Garbus examines the history of political repression in 20th-Century America, treating such inglorious episodes in our constitutional legacy as the Espionage Act of 1917, the Smith Act trials of the 1940s and ‘50s and the Wounded Knee and Pentagon Papers cases of the ‘70s. He also provides an acerbic overview of the Reagan Administration’s assault on civil liberties and its unbending support for Third World tyrannies. America emerges from Garbus’ hard-hitting survey as different from other nations, but only by degree.

With more than one-third of the world’s people living in nations that routinely employ torture, the international human-rights climate remains as grave as ever. It comes as something of a non sequitur, therefore, that Garbus concludes this otherwise brilliant disquisition with the prediction that the world will one day accept a globally enforceable bill of rights modeled after the U.N.’s Universal Declaration of Human Rights. Such optimism, regrettably, is neither supported by current trends nor Garbus’ own chilling experiences. Indeed, if Garbus has proven anything, it is that politics and power--not law--determine in the last analysis who will be branded as traitors and who will be prosecuted as fallen heroes.