Hong Kong Witness Protection Ordinance 2000

“Witness” means—(a) a person who has given, or who has agreed to give, evidence on behalf of the HKSAR in proceedings for an offence;(b) a person who has given, or who has agreed to give, evidence otherwise than as mentioned in paragraph (a) in relation to the commission or possible commission of an offence;(c) a person who has provided a statement or other assistance to a public officer in relation to an offence;(d) a person who, for any other reason, may require protection or other assistance under the witness protection programme