If the mistake is an unfortunate lack of recognition of a member of Congress, that mistake was made by the police officer. Therefore the police officer was at fault.
You can't have it both ways, Nancy.
Unless she was trying to say that Cynthia McKinney does not recognize she is a member of Congress, and therefore does not act appropriately. I guess an argument could be made for that. I don't think that was Pelosi's point, however.
McKinney also wasn't wearing her "members" pledge pin, as I recall from previous accounts.