The assessment against a defendant of the full loss suffered by a plaintiff regardless of the extent to which other parties shared in the wrongdoing is called:

Joint and several liability.

Explanation:

The joint and several liability establishes that assessment would be conducted against a defendant of all the losses or damages despite of the plaintiff's share of the liability/wrongdoing. In joint and several liability, two or more parties share the responsibility of the lawsuit. Every party is liable to the repayment of the total damage and the plaintiff may collect the damage repayment from any or all of them.