Is it legal to hunt big game with a crossbow in Idaho?

Yes, but with restrictions and only in certain hunts. You may NOT use a crossbow in an archery-only hunt (unless you have a disabled archer permit). The rules do allow the use of a crossbow in an "any-weapon" hunt or a short-range weapon hunt. In hunts where crossbows are allowed, you must adhere to the archery equipment restrictions that apply to archery hunting, listed in the current Big Game Seasons and Rules booklet. You must also use a crossbow that provides at least 150 lbs of draw weight.