Unscrupulous

unethical dishonest corrupt wicked unfair unprincipled deceitful shady questionable degraded degrading disgraceful illegal improper selfish base crafty sly scheming mercenary two-faced underhanded underhand sinister slippery dishonorable scandalous shameless crooked perfidious exploitative self-seeking unworthy venal recreant ruthless shifty low-down arrant petty conscienceless unconscientious unconscionable wrongful casuistic