Sentence:  They have not employed spies, nor been voluntary or involuntary witnesses of misdeeds or played "<WSD>bopeep</WSD>" through key-holes or from step-ladders through transom windows, upon the privacy of their political adversaries. 
Meaning of the word marked with <WSD> tags:  The act of looking out suddenly, as from behind a screen, so as to startle someone (as by children in play), or of looking out and drawing suddenly back, as if frightened.