One who shifts or reassigns the blame or responsibility (for something) to another person, group, or thing. Every politician becomes a buckpasser when they fail to deliver on their promises.Maybe instead of being a buckpasser, you should have a think about what you could be doing to improve your performance.
buckpasser
n. someone who cannot accept the responsibility for something. (see also pass the buck.) When something really goes wrong, everybody suddenly becomes a buckpasser.