What research methods did Laud Humphreys use in his research on tearooms?

Laud Humphreys employed participant observation and covert surveillance in his research on tearooms, where he studied anonymous sexual encounters between men in public restrooms. He acted as a "watchqueen," observing interactions without the participants' knowledge. Additionally, he conducted follow-up interviews with some of the men to gather further insights into their lives and motivations, all while maintaining their anonymity. This mixed-method approach allowed him to explore the complexities of sexual behavior and social identity.