Dr Steven Barrett from Massachusetts Institute of Technology explains more about the findings of his report and how he came to his conclusions:
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The oil has affected wildlife and boat owners have been told not to move their vessels to avoid spreading it.
Fearing for public safety, PC Chegwin pushed her in the chest in a defensive manner, not knowing she had extensive breast surgery.
Mr Davis is chair of planning and was given meals at top restaurants, trips to the theatre and tickets to the Centre Court at Wimbledon.