**is considered beyond reproach**

> **beyond reproach**  Blameless, faultless, as in Jean's conduct at school is beyond reproach. The phrase employs the verb to reproach in the sense of "censure or rebuke," a usage dating from the early 1500s.  
> — [The American Heritage® Dictionary of Idioms by Christine Ammer][1]

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>**reproach** &mdash; [...] reprochen "to rebuke, reproach," from Anglo-French repruchier, Old French reprochier **"upbraid, blame, accuse, speak ill of,"** [...]<br>  &mdash; [etymonline.com][2]

**EDIT:**
Originally this answer was simply **beyond reproach** though, as commenters said, this implies subject is in fact perfect, hence added the prefix **"is considered"** as suggested by @jasper


  [1]: http://idioms.thefreedictionary.com/beyond+reproach
  [2]: http://www.etymonline.com/index.php?term=reproach