Environmental campaigners Greenpeace have been fined £80,000 for breaches of a Court of Session interdict against it boarding or approaching an oil rig in the North Sea – but its director has been spared prison as the judge, Lady Wolffe, said she would "exercise leniency".

The incidents took place in June last year as Greenpeace attempted to prevent the BP rig Paul B Lloyd, Jr from being towed from the Cromarty Firth to the Vorlich field. Despite BP obtaining an interim interdict, two protestors boarded the rig and unfurled a banner on 14 June, and on 16 June two Greenpeace boats approached the rig within the 500m exclusion zone set by the interdict, with a view to boarding it, but did not succeed in boarding. A total of 14 people were arrested.

Although Greenpeace argued that no contempt had been committed, Lady Wolffe had "no hesitation" in including that it had. "Without Greenpeace’s active support and resources none of those who boarded or approached the rig would have been able to do so", she stated. "While the individual activists purport to take sole responsibility, I find that they acted with the full knowledge, consent and support of Greenpeace, and in furtherance of Greenpeace’s objectives. In my view, Greenpeace’s knowledge and their active and essential support preclude their argument that the final decision of the individual activist breaks the chain of events Greenpeace set in train or relieves them of ultimate responsibility."

With respect to Greenpeace's human rights arguments, "I find that the imposition of a sanction in respect of Greenpeace’s contempt of court is necessary in a democratic society in pursuit, first and foremost, of the aim of maintaining the court’s authority [European Convention, article 10.2]. It is fundamental to the rule of law that court orders are obeyed. Greenpeace’s admitted conduct was in wilful disobedience of the order. I have also found the imposition of a sanction necessary for the protection of the rights and freedom of others (article 11.2). The imposition of a sanction is therefore proportionate in a Convention-relevant sense."

Lady Wolffe warned that she had "considered very carefully" whether to impose a prison sentence on executive director John Sauven, who had "authorised the action from the start and was in every sense the controlling mind and will of Greenpeace in their support of the action". This would have been "within the range of proportionate sanctions". However, "in exercise of my discretion, and having regard to the whole circumstances, I intend to exercise leniency and confine this court’s sanction to a fine of Greenpeace".

This was a serious breach and merited a substantial fine, which in the circumstances would be £80,000 to cover both breaches.

Click here to view the sentencing statement.