  Blameworthiness of an agent or a coalition of agents is often defined in
terms of the principle of alternative possibilities: for the coalition to be
responsible for an outcome, the outcome must take place and the coalition
should have had a strategy to prevent it. In this article we argue that in the
settings with imperfect information, not only should the coalition have had a
strategy, but it also should have known that it had a strategy, and it should
have known what the strategy was. The main technical result of the article is a
sound and complete bimodal logic that describes the interplay between knowledge
and blameworthiness in strategic games with imperfect information.
