Fish & Fish Ltd operates a tuna farm off the shores of Malta and is regulated by the International Conference for the Conservation of Atlantic Tuna, which imposes quotas on tuna fishing. Fish & Fish was towing cages of live bluefin tuna from Libya to its fish farm when its vessel was rammed by the Steve Irwin (remember him?), owned by Sea Shepherd UK (SSUK), an environmental group, as part of its 'Blue Rage' campaign. One of the tuna cages was damaged, and Sea Shepherd divers released over half of the total catch into the sea. Fish & Fish sued for damages in trespass and/or conversion. But whom to sue? Sea Shepherd is essentially a group of charities in a number of countries, and while the Steve Irwin was owned by the UK branch, the operation in question had been organised by the US charity, Sea Shepherd Conservation Society (SSCS), and its founder, Paul Watson.

The focus of the case by Fish & Fish was that SSUK, SSCS and Watson had acted with a common design to cause injury; SSUK's role in that was to make the vessel Steve Irwin available to its joint tortfeasors and by paying for the operation and its crew through soliciting donations. The trial judge held that SSUK could not be said to be a joint tortfeasor with SSCS and Watson because, while it had a similar design, it did not join or share in a common design to injure Fish & Fish. While SSUK was legal owner of the Steve Irwin, it was beneficially owned and operated by SSCS. As a result, SSUK did not even facilitate the commission of the others' torts, and its participation was too 'remote in time and place' to make it a joint tortfeasor with them. The trial judge also rejected the argument that Watson was the controlling mind of all Sea Shepherd charities. Fish & Fish's appeal was allowed: Fish & Fish Ltd v Sea Shepherd UK, [2013] EWCA Civ 544. Beatson J noted that mere facilitation (even knowing facilitation) of another's tort will not be enough to make one a joint tortfeasor with that person. For that liability to arise, there must be (a) a common design that one or more parties will perpetrate a tortious act and (b) the alleged joint tortfeasor (here, SSUK) must itself do acts in furtherance of that common design. So, merely making the boat available won't get you there. The joint tortfeasor need not be physically present, however, nor is it necessary to show that it played an 'effective' or 'essential' part in the common design, as long as it undertook 'some act' (more than minimal) in furtherance of the common design. Cases which focus on 'effective', 'essential' or 'real significance' as criteria do so as part of the determination whether there was a common design, not the 'acts in furtherance' analysis. On the facts, the trial judge was wrong to conclude that SSUK and SSCS had no common design to disrupt tuna fishing, and wrong to say that SSUK's participation in that disruption was minimal or of no real effect. SSUK raised the funds that made the Blue Rage campaign possible and had certainly joined in the common design to put it into effect.