Deepwater Horizon
Accident Investigation Report
September 8, 2010
This is the report of an internal BP incident investigation team. The report does not represent
the views of any individual or entity other than the investigation team. The investigation team
has produced the report exclusively for and at the request of BP in accordance with its Terms of
Reference, and any decision to release the report publicly is the responsibility of BP. It has not been
prepared in response to any third party investigation, inquiry or litigation.
In preparing this report, the investigation team did not evaluate evidence against legal standards,
including but not limited to standards regarding causation, liability, intent and the admissibility of
evidence in court or other proceedings.
This report is based on the information available to the investigation team during the investigation;
availability of additional information might have led to other conclusions or altered the team’s
findings and conclusions.
At times, the evidence available to the investigation team was contradictory, unclear or
uncorroborated. The investigation team did not seek to make credibility determinations in such
cases. In evaluating the information available to it, the investigation team used its best judgment
but recognizes that others could reach different conclusions or ascribe different weight to
particular information.
In the course of the investigation, members of the team conducted interviews, and this report
draws upon the team members’ understanding of those interviews. The investigation team did
not record or produce verbatim transcripts of any interviews, nor did the team ask interviewees to
review or endorse the notes taken by the interview team members. There were at least two team
members present during each interview and, in utilizing information gathered from interviews, the
team has taken into account the presence or absence of corroborating or conflicting evidence from
other sources.
The report should be read as a