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Plausible deniability is the term given to the creation of loose and informal chains of command in governments and other large organizations. In the case that assassinations, false flag or black ops or any other illegal or otherwise disreputable and unpopular activities become public, high-ranking officials may deny any connection to or awareness of such act, or the agents used to carry out such act.

In politics and espionage, deniability refers to the ability of a "powerful player" or actor to avoid "blowback" by secretly arranging for an action to be taken on their behalf by a third party—ostensibly unconnected with the major player.

More generally, "plausible deniability" can also apply to any act that leaves little or no evidence of wrongdoing or abuse. Examples of this are the use of electricity or pain-compliance holds as a means of torture or punishment, leaving little or no tangible signs that the abuse ever took place.
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I would highlight the ability to avoid...as the core meaning of the term as far as politics are concerned.

Please refer to this forum discussion about the term, could be really useful:

http://www.translatum.gr/forum/index.php?topic=9409.0