When someone brings up an old problem in a friendship or relationship to distract from the issue at hand. Similar to a "Red Herring", except that it is an old issue. This usually leads to an escalation in the argument.
husband: Why did you let that guy give you his phone number? You should have just said "I'm married".
wife: oh come on! you flirted with my friend Jane at that Belle and Sebastian concert.
husband: that was 5 years ago and I already said sorry for that like a thousand times! You always dig up dead herrings whenever I call you on your bullshit!!!