i just need to go back to the story about the guy in training for vista support, who repeatedly asked about how to stop physical attackers, and the eventual response from the trainer:

"scenarios where the bad guys can actually physically get a hold of the computer are not supported."

and, it's actually kind of an old trope.

so, my attacker is my landlord and appears to also be a police officer of some sort. he can physically touch the computer, when i am out. there is really no feasible defence.

i can only shame the officers into knocking it off.