show up as

show (someone or something) up as (something)

To reveal someone's or something's true nature, character, or properties. The books shows up the CEO as a megalomaniac only concerned with increasing his own wealth and power. The senator showed the legislation up as an attempt to enrich the nation's wealthiest citizens.
See also: show, up
Farlex Dictionary of Idioms.

show someone up as something

to reveal that someone is really something (else). The investigation showed her up as a fraud. The test showed up the candidate as unqualified.
See also: show, up
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • show (someone or something) up as (something)
  • show up
  • the blame for (something)
  • cook the books
  • blame for
  • blame for (something)
  • blamed
  • be under suspicion
  • catch a tiger by the tail
  • be in the right spot at the right time