LOL - this wiki extract seems straight out of Yes Minister I can imagine Sir Humphrey Appleby speaking this:
"Plausible deniability is, at root, credible (plausible) ability to deny a fact or allegation, or to deny previous knowledge of a fact. The term most often refers to the denial of blame in (formal or informal) chains of command, where upper rungs quarantine the blame to the lower rungs, and the lower rungs are often inaccessible, meaning confirming responsibility for the action is nearly impossible. In the case that illegal or otherwise disreputable and unpopular activities become public, high-ranking officials may deny any awareness of such act or any connection to the agents used to carry out such acts."
