Often yes, for public parks, streets, amplified sound or open flames; contact the local authority well in advance.
Informing police helps with safety, and an investigator speaking signals the case is still active, if the agency agrees.
Around thirty to forty-five minutes is usually enough for reflections, a moment of silence and an appeal for information.
Media coverage, flyers and appeals can reach witnesses whose circumstances have changed, prompting them to contact the tip line.
Send a short advisory a week ahead with details, a photograph and a contact, and choose one family spokesperson.