geneva u.n. torture investigator voice concern wednesday call republican candidates u.s. presidential race authorize water-boarding interrogate detainees note illegal domestic international law republican candidate donald trump soften stance torture last friday say would order u.s. military break international laws treat terrorism suspect night indicate might order u.s. military break law interrogation tactics include waterboarding trump rival number two republican primaries senator ted cruz texas say last month would allow limit use practice say believe waterboarding meet international definition torture candidates unite state discuss whether waterboarding torture actually promise bring back bring even harsh techniques juan mendez u.n. special rappporteur torture tell news brief geneva bush administration allow use waterboarding practice pour water cloth cover detainee face mimic sensation drown around conflict iraq afghanistan president barack obama ban days take office 2009 bush administration withdraw torture memos discover things happen matter policy mendez say even republican administration already recognize things illegal illegal matter international law illegal matter constitutional law unite state illegal matter military law ... immoral anyway say speak u.s. citizen rather u.n. role say yes think damage stand unite state law-abiding nation example state fight crime terrorism within strictures rule law seriously damage kind rhetoric senate intelligence committee release report 2014 despite objection republicans detail call torture tactics use central intelligence agency include extensive use waterboarding u.n. torture envoy concern water-boarding rhetoric u.s. race