BP in the dock: the case explained The 18 months since have seen Judge Barbier keep the legal wheels turning on a case that has already amassed more than 7,000 exhibits and 300 depositions. The process has rarely strayed into the public eye. That will change on Monday when C268, a 100ft-long courtroom in downtown New Orleans, opens its doors for the start of a trial tasked with deciding who is to blame for a disaster that killed 11 people, injured many more, threatened the future of BP and soured Anglo-American relations. Then, of course, there are the main defendants: BP, Transocean (which owned the Deepwater Horizon rig) and Halliburton (the US company that cemented the Macondo oil well). The defendants add another layer of complexity because they've all sued each other, seeking either to deny any of the blame for the spill or, in the case of BP, share it. That's another judgment for Judge Barbier to make. It's what happens when a mass of lawsuits are coralled together in a process known in the US as multi-district litigation. BP is now steeled for a barrage of damaging headlines over the next few weeks. Although its lawyers, led by Andy Langan, will get the chance to examine witnesses, the company will be last to present its case. Lamar McKay, who heads BP in the US, and Mark Bly, the head of safety at the oil company, are expected to be among the first witnesses called by lawyers for the plaintiffs. Sources close to BP say they don't expect to be outlining their case for about six weeks. For those investors following from the Square Mile, the trial poses a different challenge. There's no timetable for when significant news or rulings from Judge Barbier will emerge. Shareholders will, for example, be looking for signs that he agrees with BP's contention that a number of parties were at fault. A settlement could come at any point once the trial has begun. It's an outcome that legal experts say Barbier will be trying to shepherd the parties towards. Everyone will be listening for answers to two central questions. Where does blame lie and were any of the companies guilty of gross negligence? The answer to the latter will determine whether fines to be paid are closer to $4bn or $18bn. An answer to the former will hopefully be a stage in the healing process for those families who lost loved ones on the night of April 20, 2010.