The objective of an investigation conducted by the Japan Transport Safety Board, JTSB, in
accordance with the Act for Establishment of the Japan Transport Safety Board is to determine the
causes of an accident and damage incidental to such an accident, thereby preventing future accidents
and reducing damage. It is not the purpose of the investigation to apportion blame or liability.
USN, owner of Crystal, NTSB, USCG and Philippine authorities have the right as interested parties to assist the JTSB, when JTSB collects evidences, inspects damages and interviews people.
When the draft report is ready comments of involved parties and flag states relevant to the cause of the incident are invited. These comments can be included in the final report if of interest.
Here is a typical example of a JTSB ships collision report:
http://www.mlit.go.jp/jtsb/eng-mar_report/2017/2015tk0008e.pdf