I agree with your approach to 'down putters', people who try to make you look bad in front of others. MY only experience with this was when I was yelled at in front of fellow workers for emailing something that was a bit odd that my boss had done. I resigned a couple weeks later. It later turned out that my boss had been illegally approving agreements with a contractor, both of which were discovered a couple months after I left. He was 'transferred' to a different division, the contractor went out of business and the unit he directed was shut down.