put your head in a noose

put (one's) head in a noose

To cause or ensure the ruin of one's plans, progress, or ambitions through foolish or reckless actions or words. Jeff had a real shot at winning the election, but he put his head in a noose by making those comments. Everyone knew the idea was bad, but no one was willing to put their head in a noose and criticize it during the meeting.
See also: head, noose, put
Farlex Dictionary of Idioms.

put your head in a noose

or

stick your head in a noose

If you put your head in a noose or stick your head in a noose, you deliberately do something which will put you in danger or in a difficult situation. At the risk of putting my head in a noose, I will make some predictions. I wasn't going to stick my head in a noose and speak out in the meeting. Note: A noose is a loop and knot that is tied in rope in order to hang someone.
See also: head, noose, put
Collins COBUILD Idioms Dictionary, 3rd ed.

put your head in a noose

bring about your own downfall.
See also: head, noose, put
Farlex Partner Idioms Dictionary
See also:
  • stand in (one's) own light
  • a fool and his money are soon parted
  • fool and his money are soon parted
  • fool and his money are soon parted, a
  • parted
  • be heading for a fall
  • be falling over (oneself) to (do something)
  • be falling over yourself to do something
  • doofus
  • sow the wind, (and) reap the whirlwind