Affidavits are voluntary sworn or affirmed, written statements by an individual that the maker promises is true. They are witnessed by a legislated authority. Courts require affidavits as proof that the process serving was legal. Affidavits may be written and prepared both informally as well as formally. However, in terms of process serving, HKPS would advise that the drafting of an affidavit is carried out by a lawyer qualified in the relevant jurisdiction.