hacerse el loco

1.
SpainLatin Americaneutralformal
- To pretend to be insane or mentally unstable, either literally or figuratively, often to avoid legal or moral responsibility.
2.
SpainLatin Americacolloquialinformal
- To feign ignorance, inattention, or lack of comprehension in order to avoid dealing with a problem, question, or obligation.
- To act as if one has not noticed something to escape confrontation or responsibility.

Examples:

ES: ¿ Se trata de un truco para hacerse el loco?
EN: What is this, some trick you put him up to so he'd sound crazy?
ES: Deje de hacerse el loco.
EN: Stop acting like a fool.
ES: - No sirve de nada hacerse el loco conmigo.
EN: - It's no use playing dumb with me.
ES: Ahora usted ya sabe, le acabo de dar un buen consejo para hacerse el loco.
EN: You realize that I've given you a hot tip how to get yourself declared crazy.
ES: El tapón deja de hacerse el loco y nos vamos a ver a un viticultor que se preocupa por los recolectores.
EN: The cap has stopped its crazy jig. We're off to see the only owner who cares for his gleaners.
ES: ¿Sabe lo que pienso, Sr. Capote? Trata de hacerse el loco para que lo declaren demente.
EN: You want my advice, though, Mr. Capote... he's just trying to prove the insanity defence.
ES: Tan loco como hacerse el loco.
EN: Crazy is as crazy does.
ES: - Y, en vez de hacerse el loco, podría ayudarnos a los dos.
EN: So instead of ignoring it, you could give me a hand and get her to understand.
ES: Ya que todos saben que es hijo del presidente, ¿va a hacerse el loco?
EN: Is he slacking off... now that everyone knows who he is?