(1) Before the end of 10 working days beginning with the first working day after the terms of reference, or, as the case may be, written notice has been given under regulation 17(2)—
(a) the officer concerned may provide a written or oral statement relating to any matter under investigation to the investigator, including any mitigating circumstances relevant to any such matter, and
(b) the officer concerned or the officer's police friend may provide any relevant documents to the investigator.
(2) The investigator must, as part of the investigation, consider any such statement or document and must make a record of having received it.
(3) The period of 10 working days referred to in paragraph (1) may be extended by the investigator.
(4) In this regulation “relevant document”—
(a) means a document relating to any matter under investigation, and
(b) includes such a document containing suggestions as to lines of inquiry to be pursued or witnesses to be interviewed.