You could claim ignorance that you had no idea what the box in your bag was, and thought it was a radiotherapy device that had health benefits or something. If

You could claim ignorance that you had no idea what the box in your bag was, and thought it was a radiotherapy device that had health benefits or something. If you could then prove that you bought it from a website advertising it as such and had a true belief you had no idea it jammed communications in any manner then you’d have a case of an unintentional act. Here the guy bought a jammer that has exactly one use - jamming communications. He then presumably brought it with him on purpose and intentionally hit the power button to turn it on. It’s not really a borderline case like some things could be. It’s roughly the same as shooting at someone you hate who happens to be in a crowd and hitting a bystander on accident. It’s still an intentional act and you would be guilty of intentional murder of some type if they died.