If anything it would be more a 'tu quoque' fallacy than whataboutism, because the latter tries to shift the attention to an unrelated topic, whereas here it is occupying land both times.

It certainly weakens the criticism, because the robber in your example might do the right thing, but if they really opposed robbing, surely they wouldn't do it themselves? As you said, it makes them a hypocrite, and makes you question their motive for measuring two cases with a different yardstick.

[–] SoulWager@lemmy.ml 3 points 4 days ago* (last edited 4 days ago)

OOP smells like a pro-putin propaganda account. Someone else doing something bad doesn't make your own acts of murder any more justifiable, especially when you're murdering someone completely different than the wrongdoer.

[–] wwb4itcgas@lemm.ee -4 points 5 days ago

Sure, but to my mind the question is: How does robber #2 pointing out that robber #1 is himself a robber excuse the actions of robber #2?