When can a police officer claim the official information privilege over the location of a surveillance site?

This official information privilege extends to the location of a police surveillance site if the court determines that the need for confidentiality in a particular case outweighs the necessity of disclosure. (See People v. Haider (1995) 34 Cal.App.4th 661, 664; People v. Montgomery (1988) 205 Cal.App.3d 1011, 1019.) "'"Like confidential informants, hidden observation posts may often prove to be useful law enforcement tools, so long as they remain secret. Just as the disclosure of an informant's identity may destroy his [or her] future usefulness in criminal investigations, the identification of a hidden observation post will likely destroy the future value of that location for police surveillance. The revelation of a surveillance location might also threaten the safety of the police officers using the observation post, or lead to adversity for cooperative owners or occupants of the building."'" (Montgomery, at p. 1019.)

When an officer asserts the official information privilege in response to a question about a police surveillance location in a criminal case, the defendant must make a prima facie showing that disclosure of the location is appropriate. (People v. Montgomery , supra, 205 Cal.App.3d at p. 1021.) When a prima facie showing is made, the court should hold an in camera hearing with the officer claiming the privilege. (Ibid.) If the court determines that the privilege applies, it "shall make such order or finding of fact adverse to the public entity bringing the proceeding as is required by law upon any issue in the proceeding to which the privileged information is material." (Evid. Code, 1042, subd. (a).)