Not sure if I explained myself properly
The person filling out the form is required to check this box manually to agree to the terms and conditions Before it can be sent. So as soon as the form is loaded, the checkbox needs to be empty.
No matter what I try, the box is always checked by default. The form therefore passes validation and can be sent but this causes a potential legal glitch: The form makes the assumption the user has ALREADY agreed to the terms and conditions.