**establish one's bona fides**

**bona fides** (plural noun)

> 1.  good faith; honesty, sincerity, reliability, etc.
> 2.  proof or proofs of honesty, genuineness, etc.  
> [*Webster’s New World College Dictionary*][1]


> 1: good faith : sincerity  
>2: the fact of being genuine —often plural
> in construction  
>3: evidence of one's good faith or genuineness —often
> plural in construction  
>4: evidence of one's qualifications or
> achievements —often plural in construction  
>[M-W][2]

--------------------------------

> To help **establish his bona fides** as a leader of the underworld he
> provided a fifteen-foot-high floral tribute at the funeral of a slain
> gangster, and to protect himself he bought an automobile with armor
> plating and bulletproof glass.  
>[Marc Mappen; *Prohibition
> Gansters*][3] (2013)
 
> He shoots a policeman to **establish his bona fides** with the
> gangsters, and later cold-bloodedly sends the chief of police to his
> death.  
>[Brian Docherty; *American Crime Fiction*][4] (1988)

> Many gang and low-level cartel members met in prison, where trust was
> built over time and where **their "credentials" and bona fides were
> established**.  
>[Paul Rexton Kan; *Cartels at War*][5] (2012)
 
> We brought in an undercover agent named Tony out of Chicago who the
> New York gangs didn't know, a wiseguy lookalike right out of central
> casting. We made sure he made the rounds to all the bars and clubs
> frequented by made guys, always in the company of our boy Hackey to
> **establish his bona fides**.  
>[Dan Addario et al.; *Chasing the Dragon*][6] (2019)


  [1]: https://www.collinsdictionary.com/us/dictionary/english/bona-fides
  [2]: https://www.merriam-webster.com/dictionary/bona%20fides
  [3]: https://books.google.com/books?id=qUwQAAAAQBAJ&pg=PA53&dq=gangster%20establish%20his%20bona%20fides&hl=en&newbks=1&newbks_redir=0&sa=X&ved=2ahUKEwjF8_6d5Z2JAxXHEVkFHbnTKgIQ6AF6BAgPEAI#v=onepage&q=gangster%20establish%20his%20bona%20fides&f=false
  [4]: https://books.google.com/books?id=4u-uCwAAQBAJ&pg=PA62&dq=gangster%20establish%20his%20bona%20fides&hl=en&newbks=1&newbks_redir=0&sa=X&ved=2ahUKEwjF8_6d5Z2JAxXHEVkFHbnTKgIQ6AF6BAgNEAI#v=onepage&q=gangster%20establish%20his%20bona%20fides&f=false
  [5]: https://books.google.com/books?id=g6fLcqJOiN4C&pg=PT60&dq=gangster%20establish%20his%20bona%20fides&hl=en&newbks=1&newbks_redir=0&sa=X&ved=2ahUKEwjF8_6d5Z2JAxXHEVkFHbnTKgIQ6AF6BAgJEAI#v=onepage&q=gangster%20establish%20his%20bona%20fides&f=false
  [6]: https://books.google.com/books?id=_9CCDwAAQBAJ&pg=PT78&dq=%22establish%20his%20bona%20fides%22%20for%20the%20mob%20bosses&hl=en&newbks=1&newbks_redir=0&sa=X&ved=2ahUKEwjm0cWP6Z2JAxUVFlkFHclACzoQ6AF6BAgJEAI#v=onepage&q=%22establish%20his%20bona%20fides%22%20for%20the%20mob%20bosses&f=false