Oil giant BP is due today to begin the second phase of the civil trial over its 2010 Gulf of Mexico oil spill.
The Deepwater Horizon rig explosion killed 11 workers and blackened hundreds of miles of beaches.
Today, the debate will be on how much oil was spilt. The US government will argue that, over 87 days, 4.2m barrels of oil were released into the sea - that's a quarter of the amount of oil used across America in a day. BP will argue that the figure was closer to 2.45m barrels.
The first phase of the trial focused on whether BP and its contractors were guilt of gross negligence; this phase rests on the Clean Water Acts fine which could see the company fined between $1,100 to $4,300 per barrel if they are found guilty of gross negligence.
The company took a tumble with the spill, with less profitable operations and spend on environment clean-up and compensation to victims coming in over $42bn.