Exxon Valdez oil spill State of Alaska's "Exxon Valdez" Oil Spill Trustee Council, the National Oceanic and Atmospheric Administration and environmental groups such as Greenpeace and the Sierra Club. Multiple factors have been identified as contributing to the incident: Captain Joseph Hazelwood, who was widely reported to have been drinking heavily that night, was not at the controls when the ship struck the reef. However, as the senior officer, he was in command of the ship even though he was asleep in his bunk. In light of the other findings, investigative reporter Greg Palast stated in 2008, "Forget the drunken skipper fable. As to
Oil tanker instrument, Shell consulted the "London Tanker Brokers’ Panel (LTBP)". At first, they divided the groups as "General Purpose" for tankers under ; "Medium Range" for ships between 25,000 and and "Large Range" for the then-enormous ships that were larger than . The ships became larger during the 1970s, which prompted rescaling. The system was developed for tax reasons as the tax authorities wanted evidence that the internal billing records were correct. Before the New York Mercantile Exchange started trading crude oil futures in 1983, it was difficult to determine the exact price of oil, which could change with every contract.