Garzon, 56, faces the first of three trials in Supreme Court in Madrid that could bar him from serving as an investigative magistrate for as long as 17 years, which would end his career, The Daily Telegraph of Britain reported Tuesday.
Garzon's supporters, who include human rights groups in Spain and throughout the world, call the accusations politically motivated and say they were triggered by his attempt to investigate crimes associated with human rights abuses committed under the dictatorship of Gen. Francisco Franco.
The first trial involves accusations Garzon abused his power by approving illegal wiretaps of conversations between defense attorneys and their clients, suspects in a corruption case. The Telegraph said the corruption case implicates members of the conservative Popular Party, Spain's ruling party.
In a second trial, slated for this month, Garzon faces accusations he exceeded his judicial authority when he attempted to open an investigation into the death and disappearance of some 110,000 people during Franco's regime. Garzon dropped the investigation after state prosecutors called into question his jurisdiction, saying the investigation violated a 1977 amnesty.
In the third case, Garzon faces allegations he dropped an investigation into Salander bank after receiving money from the bank.
A crowd of supporters met Garzon outside court Tuesday, including human rights groups and relatives of victims killed by Franco forces.
"What bitter irony that Garzon is being prosecuted for trying to apply at home the same principles he so successfully promoted internationally," said Reed Brody, a spokesman for Human Rights Watch.