汚きたない手てを使つかう

expression, godan verb (-u)

play a dirty trick; use underhanded methods; hit below the belt

Idiomatic expression for acting dishonestly or unfairly, especially in competition or conflict. Often implies a deliberate, sneaky tactic.

• 彼かれは選せん挙きょで汚きたない手てを使つかって勝かった。

  He won the election by using dirty tricks.

• そんな汚きたない手てを使つかうなんて、許ゆるせない。

  I can't forgive you for using such underhanded methods.