The International Commission of Jurists on condemned the wiretapping conviction of renowned Spanish judge Baltasar Garzon on Thursday as "deplorable".

It said Garzon, who was suspended from office for 11 years for ordering illegal recordings of conversations between corruption suspects and their lawyers, had been prosecuted simply for doing his job.

"The conviction of Judge Garzon in this case is the deplorable conclusion of a criminal proceeding that should have never been initiated in the first place," ICJ president Pedro Nikken said of the Spanish supreme court ruling.

"Garzon has been removed from the bench for interpreting the law and rendering a decision but whether or not one agrees with the interpretation and decision, this is precisely what being a judge is about."

Garzon is also waiting judgment in a second trial for trying to investigate atrocities of the Franco era, in an alleged breach of an amnesty.

His defenders say both trials are politically motivated bids to stop him prosecuting crimes committed during Spain's 1936-1939 Civil War and the subsequent dictatorship of General Francisco Franco.

"One might wonder to what extent this sentence is just a way to silence Garzon," said Nikken.

The Geneva-based ICJ is made up of about 60 lawyers, including senior judges, tasked with ensuring respect for international human rights standards through the law.