[1] He had previously been the leader of Basque separatist youth organisation Jarrai [ca; es; gl] in the 1990s and had stood unsuccessfully as a candidate for Herri Batasuna in the 1995 local elections.
[8] In 1994, when Spanish police dismantled the Nafarroa commando unit of ETA, they raided Pla's home in the Ermitagaña district of Pamplona, but failed to find him.
[9] On 28 July 2000, Pla was one of two people arrested in Zaragoza, charged with planning to assassinate the Mayor of the city, José Atarés, by placing a sticky bomb on his car.
[9] In June 2001 Pla was found guilty and sentenced to six years in prison and fined 90,000 Pesetas for the use of false documents.
[12] In 2010, Pla was rearrested, accused of having passed messages from the group's leadership to a group of lawyers representing the organisation[13] At the time of his arrest, the Spanish Interior Ministry also believed Pla to be responsible for managing the relationships between the ETA leadership in France and ETA prisoners, which included assisting with prison escape attempts and aiding fugitives.
[2] Subsequently, Pla was involved in the peace process which followed the ceasefire declaration as one of the main negotiators[16] and was given sanctuary in Norway.