Monitronics cheated my senile mother Internet

When my mother died this week (July 2012), I found that Monitronics had gotten her to sign a 3 year contract in 2011 and they were deducting automatic payments from her bank account. For several years, she has been very confused and I've paying her bills, all of which are sent to me. I can only imagine that they came to the door and pretended not to notice her state of mind. She already had a five-year contract in place with Pinnacle and a fully operational system that I have been faithfully making the payments on. As far as I can see at the house, only Pinnacle's system is there -- which means Monitronics has been collecting $40 per month for more than a year without every doing anything, including placing equipment in her house. They of course want a death certificate to cancel the contract. I'm not terribly worried; the bank account they were taking money from has been closed, and I'll see them in hell before they get another penny. What a disgusting business practice -- preying on old, helpless ladies!