The roots of the word privilege lie in the words "private law", meaning one set of rules apply to one group, and a wholly different set apply to another group. Historically, we've seen that idea in high justice (for nobility) and low justice (for ordinary people), and in the ecclesiastical court system that was applied to priests rather than allowing them to be tried by the government. Although America was founded in part as a rejection of those separate systems of law, we still have vestiges surviving today, as in this recent ruling that John Conyers, a Democrat representative in Michigan, need not follow the law when obtaining signatures to be placed on the ballot for his party's primary.
Specifically, the law says signatures must be gathered by a registered voter within the state. Conyers didn't bother to check, and ended up with a large number of signatures collected by someone who wasn't. Without those signatures, he didn't qualify for the ballot in his party primary; but mere hours after the Secretary of State ruled that Conyers did not qualify for the ballot, a judge overruled the decision despite precedent to the contrary. The previous politician was a Republican, the more recent case a Democrat. That shouldn't matter, but apparently it does.