Scapegoat. This is a person who is blamed for the failures of others.
Fall guy. This is the person who is set up to take the blame.
Take the fall. A person who takes the fall accepts the blame, often for something others did.
Pass the buck. To pass the buck is to push responsibility on to someone else.
Point fingers. People who point fingers blame others.
The blame game. In the blame game, everyone blames someone else.
Heads will roll. People will lose their jobs because of the failure.
Left holding the bag. This person is blamed after the others got away.