'Tax evader' but much more commonly we say "tax dodger" or 'tax cheat" which are more informal. Formal or legal writing might say "a person who was guilty/convicted of tax evasion." The Australian Tax Office uses the term "tax cheats" on their website which sort of surprises me since it is quite informal. https://www.ato.gov.au/General/Tax-evasion-and-crime/Dealing-with-tax-crime/

A politician :)

A tax attorney.

Hahaha... appart from that, Peter! :) Thanks, Nicole!

We say tax evader in the US or simply say "fraud" (more like a slang).