When (if ever) is it ok to stage a workplace Coup d'Etat?

The first thing you think of with that term is the violent overthrow of a government, but it also has the meaning of a sudden decisive exercise in force.

A group of co-workers are united in their opinion that the person directly above them is incompetent and unethical. It is the general consensus that this person does not ‘stand up’ for the group, adds additional responsibilities to the group without regard of their ability to do handle the extra workload, has botched communications with customers, has acted unethically within the organization and also in situations which affect customers of the organization.
The laundry list of complaints is extensive and the points are valid. Somehow, this person continues to fly under the radar of upper level management.

Is it ever a good idea for the collective to bring their documentation of the ethical lapses and incompetence to upper management?