To have one's actions be controlled by another individual(s) due to inebriation, cognitive impairment or death all whilst maintaining the outward pretence of autonomy.
Derivation: From the film 'Weekend At Bernie's' where the titular protagonist was puppeteered through a number of jolly japes whilst being deceased.
Joe was so drunk that he needed to be Bernied all the way home.
A phrase to describe someone receiving the maximum allowance from the UK Welfare System. In the UK these are know as Social Benefits, hence being on "Full Benefits" or "Full Bennies"