20.—(1) Before the end of 10 working days starting with the first working day after the notice is given under regulation 19(1) (unless this period is extended by the investigator)—
(a)the officer concerned may provide a written or oral statement relating to any matter under investigation to the investigator; and
(b)the officer concerned or the police friend may provide any relevant documents or other evidence to the investigator.
(2) The investigator must—
(a)as part of the investigation, consider any such statement, document or other evidence; and
(b)make a record of having received it.
(3) 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.