Nondiscrimination rules—statutes, regulations, and soft law protections—are critical for reducing health and health care disparities. Although scholarship has interrogated how nondiscrimination rules affect behavior by discriminators, comparatively little has considered how protections can affect choices made by members of protected groups. A number of states and some interpretations of federal law protect people from discrimination on the basis of sexual orientation. This Article seeks to identify relationships between actual state law, perceived state law, and experiences of discrimination and medical mistrust. This Article reports the results of a national cross-sectional survey of over 3,000 men using Grindr to meet male partners. Participants scored comparable to chance in knowledge about state nondiscrimination protections, with “optimistic errors” (erroneous beliefs that one was protected) significantly more common than pessimistic errors. Perceptions of protection were significantly correlated with lower medical mistrust and greater uptake of care, as well as lower perceived barriers to disclosure and care-seeking. Actual state law protections, however, were significant predictors of having had discussions with providers that depended on disclosure of sexual behavior or orientation. Building on these results, this Article considers pathways by which nondiscrimination law may exert welcome mat (and “unwelcome mat”) effects.