… is from page 648 of Book IV, Chapter viii of the 1981 Liberty Fund edition of Adam Smith’s magisterial 1776 book, An Inquiry Into the Nature and Causes of the Wealth of Nations:
But the cruellest of our revenue laws, I will venture to affirm, are mild and gentle in comparison of some of those which the clamour of our merchants and manufacturers has extorted from the legislature, for the support of their own absurd and oppressive monopolies. Like the laws of Draco, these laws may be said to be all written in blood.