BARCELONA -- On Friday, May 14, Spanish judge Baltasar Garzón, known around the world for attempting to bring dictators to justice, was told he will now face trial for attempting to do the same in his own country. If found guilty, the 54-year-old examining magistrate could be removed from his job for up to 20 years.

The blow has been expected ever since early April, when Spain's Supreme Court accused Garzón of 'knowingly exceeding his powers' during his 2008 attempt to investigate alleged crimes against humanity carried out during the country's 40-year dictatorship under General Francisco Franco. The case is causing consternation both in Spain and abroad, mainly because it was brought by three ultra right-wing organizations. Among these were the Falange Española, the Fascist party once presided over by Franco himself -- whose military coup of 1936 sparked the bloody, three-year Spanish Civil War, and culminated in a long dictatorship that ended only with his death in 1975. Historians estimate that Franco's postwar reprisals cost the lives of 100,000 people.

Garzón's many supporters have responded to the case with dismay, moved by its outrageous symmetry: a highly respected judge brought to trial, for attempting to try crimes, on an accusation by the disciples of the regime that perpetrated those crimes in the first place.

Throughout April the judge's pending suspension and trial has spawned j'accuse editorials in the New York Times and the Guardian, among many others. Only the Wall Street Journal dissented, heavily critical of Garzón's previous attempts to extradite Chile's former dictator, General Augusto Pinochet.

In Spain, meanwhile, the Garzón case has triggered some of the angriest scenes in recent years, sharply dividing public opinion, setting the political parties at loggerheads, and questioning the so-called "pact of silence" between the country's left and right on crimes committed by the dictatorship, which has been the consensus underpinning Spain's 32-year-old democracy.

So what, exactly, is Garzón alleged to have done wrong?

His far-right accusers, and now the Supreme Court, allege that attempting to criminalize Franco for crimes against humanity falls foul of Spain's 1977 Amnesty Law, and that by declaring himself nevertheless competent to proceed, Garzón had perverted the course of justice.

Nonsense, say his supporters: The trial is an unholy alliance between the far right and a political establishment that does not want to see the Franco regime tainted -- in part because the fathers and grandfathers of many of today's public figures served in it.

If that was the intention, it seems to have backfired. In aiming to keep the past untouched, Garzón's enemies may have done the opposite: The rallies in his favor have been well attended and multi-generational, and anyone observing them can't help feeling a major social movement has been unleashed.

Such an effect would be typical of a judge whose showmanship, and predilection for heroic, almost epic causes, is legendary. What has now opened is only the latest, global chapter in a long running one-man show that has enthralled Spain since the 1980s. Internationally, it is a test case pitching local Amnesty laws against international laws, while for Spaniards it is a painful revisiting of their national story.

On the sunny Saturday afternoon of April 24, knowing that it was only a matter of time before the judge faced trial, the "Garzónistas" across Spain took to the streets.

In Barcelona, Spain's second city, several thousand crowded into the central Plaça Sant Jaume, pro-Garzón banners alternating with black-and-white photos of disappeared family members from the 1930s and 1940s. "Where is my grandfather?" read numerous placards, a plea that had simultaneously spread to pavement rallies outside Spain's embassies in London, Paris, Lisbon, and, several hours later, Buenos Aires.