Mo. Rev. Stat. § 565.257: Law enforcement officers viewing or photographing during investigations or in prisons for security not an invasion of privacy.

The provisions of sections 565.250* to 565.257 shall not apply to:

(1) Viewing, photographing or filming by law enforcement officers during a lawful criminal investigation;

(2) Viewing, photographing or filming by law enforcement officers or by personnel of the department of corrections or of a local jail or correctional facility for security purposes or during investigation of alleged misconduct by a person in the custody of the department of corrections or the local jail or correctional facility.