If you have even an hour or two of training in using a kubotan/yawara as an impact weapon, most multi-tools become a much more damaging weapon closed than with the knife blade out. The sort of thing you learn when you mention to sensei that you can't carry a gun at work but always have your multi tool. The cops have no way of knowing whether it has that skill or not.
For that matter, there are at least a few cheap multi tools based on a hammer, which would be even more dangerous with or without training.