get a free hand with (something)

To be allowed complete freedom to do what one wants or chooses with some particular thing. Can you believe I got a free hand from the boss with this project? Finally, I can present a campaign with my own vision! It seems inconceivable that the company would get a free hand with this funding. Surely the government ought to have some sort of control over it, right? Hold on, you didn't get a free hand with this assignment! You still have to get your topic approved by the professor.