What is the test for wearing a mask to enter a police station?

"The intruder who enters clothed in the robes of authority in broad daylight commits no less an invasion of these rights than if he sneaks in in the night wearing a burglar's mask. In some ways, entry by the authorities is more to be feared, since the citizen's right to defend against the intrusion may seem less clear. Courts should leave no doubt as to whose side the law stands upon." ( Hendler v. United States, supra, 952 F.2d at pp. 13741375.)