In People v. Knight, 323 Ill. App. 3d 1117, 753 N.E.2d 408, 257 Ill. Dec. 213 (2001), the court noted that a trial court should order an in camera hearing out of the presence of defendant and defense counsel. Knight, 323 Ill. App. 3d at 1127. During the in camera hearing, the State's witness must reveal the surveillance location from which the defendant was watched, and the State must make a preliminary showing that disclosure of the surveillance location would harm the public interests and should therefore remain privileged. Knight, 323 Ill. App. 3d at 1127. The Knight court further held that a qualified privilege exists at trial for the disclosure of a surveillance location, while noting that where a defendant's need for the location information is so great that the case against him turns almost exclusively on an officer's testimony, disclosure must almost always be ordered. Knight, 323 Ill. App. 3d at 1127-28 (the officer's testimony was uncorroborated).