How could you possibly be considered responsible for the impact something of yours has after it's been stolen?
Because that impact was your explicit intention when you designed and set up the device.
Laws are sometimes stupid.
However this assumes they will be able to trace back the device to you. If you do it properly (I guess start with not leaving 3 phones with active SIM cards inside) they won’t be able to and you can enjoy your sweet revenge.
That's like arguing that I killed myself because the person who snuck in my house used the kitchen knife I accidentally left on the counter to murder me.