The Open Thread posted at the beginning of the month has gotten really, really big, so I've gone ahead and made another one. Post your new discussions here!
This thread is for the discussion of Less Wrong topics that have not appeared in recent posts. If a discussion gets unwieldy, celebrate by turning it into a top-level post.
Closest I know is "tu quoque".
That is pretty close. If I understand them right, I think the difference is:
Tu Quoque: X is also guilty of Y, (therefore Z).
False Equivalence: (X is also guilty of Y), therefore Z.
where the parentheses indicate the major location of error.