give someone free rein

give (one) free rein

To give one complete freedom to do what one wants or chooses. "Rein" refers to the reins of a horse. Can you believe the boss gave me free rein on this project? Finally, I can present a campaign with my own vision!
See also: free, give, rein
Farlex Dictionary of Idioms.

give someone free rein

or

give someone a free rein

COMMON If you give someone free rein or give someone a free rein, you give them all the freedom they want or need to do something. Note: The reference in these expressions is to a rider using the reins to control a horse. He was given free rein to manage the project as he wished. Much to her delight, she was given a free rein to decorate the house exactly as she wanted. Note: You can also say that you allow someone free reign. The artists were allowed free rein to produce what they thought fitted the space. Note: You can also say that you have free rein. The children have free rein to choose the subjects that they want to study.
See also: free, give, rein, someone
Collins COBUILD Idioms Dictionary, 3rd ed.
See also:
  • give (one) free rein
  • give free rein to
  • give free rein to (one)
  • give full rein to (one)
  • give/allow somebody/something free/full rein
  • allow
  • allow (one) free rein
  • give (one) full rein
  • allow (one) full rein
  • free rein