NEW ORLEANS (AP) -- BP's (NYSE:BP) first witness at a trial over the deadly Deepwater Horizon disaster says the company safely drilled its Macondo well in the Gulf of Mexico before an April 2010 blowout triggered the nation's worst offshore oil spill.

Retired LSU petroleum engineering professor Adam "Ted" Bourgoyne Jr. is an expert in drilling operations. He testified Monday that crew members and BP supervisors on the rig followed "normal industry practices" before encountering problems as they tried to plug the well.

Bourgoyne said he disagrees with an expert witness for the federal government who testified earlier that BP deviated from industry standards and continued drilling despite clear signs of trouble.

The trial has entered its seventh week. It is designed to identify causes of the blowout and assign fault to the companies involved.

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