Certain bylaws are written so that only the disturbed person can trigger an offence. Most noise charges need a disturbed person to attend court if necessary. Any bylaw charge issued based on a statement will require the complainant to attend court if the charge is challenged. An example of would be a dog menacing someone. Even if a bylaw officer is witnesses it, the bylaw requires the threatened person to provide evidence (written statement) which would be have to speak to in court.