bona fides

 
Pronunciation: /ˌbəʊnə ˈfʌɪdiːz/

noun

[mass noun]
  • a person’s honesty and sincerity of intention: he went to great lengths to establish his liberal bona fides
  • [treated as plural] informal documentary evidence showing that a person is what they claim to be; credentials: he set about checking Loretta’s bona fides

Origin:

Latin, literally 'good faith'