Madrid (CNN) -- Spain's Supreme Court on Monday dropped a case against the nation's best-known judge, Baltasar Garzon, saying the statute of limitations had expired on the alleged abuse involving some courses he taught at New York University years ago.
The ruling comes just days after a seven-judge panel at the Supreme Court convicted him in a separate case for improperly ordering wiretaps while investigating financial corruption and suspended him from the bench for 11 years.
Garzon has vowed to appeal that conviction, but many analysts say the 56-year-old judge --who became known internationally for investigating human rights abuses under the former Chilean dictator Augusto Pinochet -- may have a hard time regaining a judgeship while any appeal is pending.
Another trial against Garzon -- concerning his investigation of human rights abuses under the former dictatorship of Francisco Franco in Spain -- ended Wednesday and is awaiting a verdict from a different panel of Supreme Court judges.
Human rights groups say the three cases, especially for his investigation of Franco, amount to a vendetta against Garzon. He has been under suspension since 2010 pending the trials.
In the Supreme Court decision Monday, investigating magistrate Manuel Marchena ruled there would be no trial and charges would be dropped because the statute of limitations had expired.
In this case as well as the other two, state prosecutors had not brought charges against Garzon but private parties had. Private prosecution is allowed under Spanish law. They argued that Garzon, when teaching judicial courses at New York University in 2005 and 2006, had improperly approached some of Spain's largest companies for donations to underwrite the cost of the courses.
Some of those companies had cases pending before Garzon's court, the private prosecution alleged.
Garzon maintained his innocence -- as he has in all three cases -- and said he never solicited funds for the courses, which instead was done, he said, by a university official.
The wiretapping case was tried last month and the verdict was issued Thursday. It centered on Garzon's investigation into the financial corruption scandal known as Gurtel, for which some leading conservative politicians, among others, have recently been brought to trial.
Garzon said his wiretap orders, in early 2009, were backed by state prosecutors. He testified that he ordered the wiretaps on suspicion that suspects in the case were involved in money laundering while they were in preventative prison.
But the Supreme Court judges wrote, "The central question to be resolved in this case is related to the fundamental right of defense for the suspect, against the legitimate interest of the State to pursue crimes," the sentence said. "It is not possible to have a just process if the right of defense is essentially eliminated."
The sentence added that Garzon's investigation had the effect of "admitting practices which now are found only in totalitarian regimes where anything is considered valid to obtain the desired information."
Garzon's possible avenues for appeal include the Constitutional Court -- Spain's highest court, which rules on constitutional issues -- or to the European Court for Human Rights in Strasbourg, France.
Human rights groups, which have sent observers to the trials, consider the second case against Garzon -- for his investigation of mass graves under Franco's rule -- to be the more important one.
In that case, a small civil servants union called Manos Limpias, or Clean Hands, brought a private prosecution against Garzon, charging him with ignored an amnesty law approved in the Spanish Parliament in 1977, two years after Franco's death.
In that trial, which ended last week and is awaiting a verdict, Garzon testified that he searched but could not find any national census of how many people disappeared or their identities. So he decided to investigate because he considered those to be "permanent crimes" which still affect their descendants, since the remains have never been found.
He said he began to see evidence that there was a "systematic plan" against Franco's opponents, which he said included forced disappearances, illegal detentions and assassinations.
The military uprising in 1936 triggered the three-year Spanish Civil War. The war ended when Franco's forces defeated Republican and leftist fighters. Franco's dictatorship continued until his death.
Mass graves from the regime are still being unearthed, said Emilio Silva, from a group called Historical Memory.
Reed Brody of Human Rights Watch said last week, "This is a trial that should never have been held, but which at least served to show that Garzon acted in accordance with international law, which imposes on states a duty to investigate the worst international crimes."
"The Supreme Court should put an end to this sorry episode for Spanish justice by acquitting judge Garzon of all the charges against him," Brody added. "Investigating state killings and 'disappearances' should never be considered a crime."
Since his suspension in 2010, Garzon has been working as a legal adviser outside of Spain on human rights cases and judicial issues, including in Latin America.