US ruling will cut BP's Deepwater penalty A US judge ruled that 810,000 barrels of oil captured by BP from its leaking well in the Gulf of Mexico in 2010 should be excluded from the penalties it potentially faces, in a small victory for the UK oil group. The ruling will reduce the maximum penalty BP could have to pay under the Clean Water Act by up to $3.5bn. It comes days before the long-awaited civil trial over Deepwater Horizon begins in New Orleans. BP has said it will defend itself in the trial, having failed to reach a settlement with the US and the Gulf states. The disaster occurred in April 2010 when a well BP was drilling in the Gulf of Mexico blew out, causing a fire and explosion aboard the Deepwater Horizon rig that killed 11 men and triggering the worst oil spill in US history. The US government estimates that 4.9m barrels of oil leaked into the Gulf. But BP argued in its court filing that it captured 810,000 barrels from the broken wellhead, piped it to the surface and either shipped it to shore or burnt it off. The judge hearing the civil trial, US District Judge Carl Barbier, ruled late on Tuesday that this oil was never released into the environment and so should not be used to calculate the penalties BP faces. "The "Collected Oil" flowed from the subsurface reservoir, through the well, through the blowout preventer, and never came into contact with any ambient seawater, and was not released to the environment in any way," the ruling said. The US and BP agree that the 810,000 barrels of collected oil are not to be used in calculating the statutory maximum penalty. The ruling is positive for BP, which stated on Monday that it did not believe the captured barrels should be considered in the court's future determination of Clean Water penalties. It said the US Department of Justice "has indicated that it agrees with BP's position on this issue." Initially, it was thought BP could face maximum Clean Water penalties of $21bn if the US succeeded in proving the company was grossly negligent. This was based on the maximum potential penalty of $4,300 per barrel spilled and the government's 4.9m barrel number. Reducing it by 810,000 barrels would slash the total figure by $3.5bn. However, BP claims the 4.9m figure is overstated by at least 20 per cent. Beyond that, deducting the 810,000 barrels collected would leave a figure of 3.1m barrels for the total spilled, according to the company's calculations. BP also argues that proving gross negligence will be hard, since the accident had "multiple causes and involved multiple parties." Rupert Bondy, BP's general counsel, told the Financial Times earlier this week that the Clean Water penalty BP faces could end up being well below $5bn.