A federal judge has ruled that BP's reckless conduct resulted in the nation's worst offshore oil spill, leaving the company open to billions of dollars in penalties. US District Judge Carl Barbier's ruling today could nearly quadruple the amount of civil penalties BP could face for polluting the Gulf of Mexico with its Macondo well blowout. Barbier presided over a trial in 2013 to apportion blame for the spill that spewed oil from April 20 to mid-July 2010. Eleven men died in the explosion; BP already has agreed to billions of dollars in criminal fines. Barbier says BP bears 67% of the blame for the spill, drilling rig owner Transocean Ltd. takes 30% of the blame, and cement contractor Halliburton Energy Services takes 3%.