I want to speak up for people I like, but I don't want to burn bridges. Should I have told Tom? How should I act in the future?
Karla: "Really? Tom's always had good things to say about you."
You can't shame the shameless, but you can pleasantly decline to join them. You may end up a target, but then you probably were, anyway.
Tom doesn't need to know about Maria's sniping unless it could harm him. If he's hoping for a referral from her, you'd be justified in saying, "I dunno if she'd be my first choice for a glowing reference. You can probably do better with someone else."
Karla L. Miller writes an advice column on navigating the modern workplace. Each week she will answer one or two questions from readers. Miller has written for and edited tax publications for 16 years, most recently for the accounting firm KPMG's Washington National Tax office. You can find her on Twitter, @KarlaAtWork.