Every one of us sometime in our lives has uttered the phrase, "getting away with it scot-free." Many people have believed that the term comes from some sort of Scottish tradition or derogatory term against the Scottish people. Others have believed that it began with Dred Scot, an American slave who went to court in order to gain his freedom. In reality the etymology of the phrase has its roots as far back as 13th century medieval Europe.
The word scot is an old Scandinavian term which references the making of a payment or contribution. In England, starting near the end of the 12th century, a tax was levied against the people known as Scot and Lot. This became a well known tax among the people which was an assessment tax on households for the purpose of raising money to pay for local and some national expenses. Most of the money for these taxes was to go toward helping the poor. Being an assessment tax the more property you owned the larger the tax would be. Many of the wealthier gentlemen and nobles in the country would bribe tax collectors or withhold information for the purpose of avoiding the tax. It was not long until the term scot-free was used to describe this action by the wealthier elite. Since the Scot and Lot tax continued all the way up until 1832 the term became a common phrase within the English language.
Since the term scot refers to making a payment the use of the phrase scot-free expanded beyond just avoiding the Scot and Lot tax. The term scot began to reference ones tab at a local tavern or other entertainment type expenses. If someone paid the tab for them or the person was able to avoid paying the bill you were known to have gotten away scot-free. This simply perpetuated the term and helped integrated it into the everyday vocabulary of the common man. It is easy to see why this term is still being used today.