Section 831.21 - Other Government agencies and NTSB aviation investigations(a) Pursuant to 49 U.S.C. 1132(c) and 106(g)(1)(A) , the NTSB will provide for the participation of the Administrator of the FAA in the investigation of an aircraft accident when participation is necessary to carry out the duties and powers of the FAA Administrator.(b) Title 49 U.S.C. 1131(a)(2) provides for the appropriate participation by other departments, agencies, or instrumentalities of the United States Government in the investigation of an aircraft accident by the NTSB.(c)Rights and duties of other Federal agencies.(1) The FAA and other Federal agencies named as parties to an aircraft accident investigation will be accorded the same rights and privileges, and are subject to the same limitations, as other parties. Participation in an investigation includes the duty to timely share with the NTSB any information that has been developed by the FAA or other Federal agency in the exercise of that agency's investigative authority.(2) In exercising its authority, the FAA or other Federal agency may obtain information directly from a party to an accident or incident under investigation by the NTSB.(3) Information obtained by another Federal agency must be timely shared with the NTSB.(4) Investigative activities by another Federal agency must be coordinated to ensure that they do not interfere with the NTSB's investigation.(5) Under no circumstances may an NTSB aviation accident investigation for which the FAA or any other Federal agency has conducted fact-finding be considered a joint investigation with shared responsibility. Decisions about what information to include in the public docket will be made by the NTSB.(6) Notwithstanding the rights and duties described in paragraphs (c)(1) through (5) of this section, determining the probable cause of an accident is exclusively the right and duty of the NTSB.(d) An FAA employee designated to act by the NTSB IIC has the same authority as an NTSB investigator when conducting activities under this part. The investigation remains that of the NTSB.(e) Nothing in this section may be construed as inhibiting the FAA from proceeding with activities intended to fulfill a statutory requirement or objective, including the collection of data for safety management or enforcement purposes. Section 831.5 of this part also applies to the investigation of aviation accidents.