During his tenure, Johnson wrote the majority opinion for only two major cases: "United States v. Hudson and Goodwin" in 1812"," and "Mechanics' Bank of Alexandria v. Bank of Columbia" in 1820. In "U.S. v. Hudson", the Court held that federal courts lacked the power to develop common law crimes, a decision which was celebrated by Jeffersonians. However, in "Mechanics' Bank," the Court established federal common law precedent that a federal judge could hear parol evidence to explain a written contractual agreement if the agreement's meaning was ambiguous. Johnson also wrote over a hundred majority opinions for "arcane land, admiralty, and insurance cases" as well as numerous concurrences. Following 1820, Johnson wrote fewer majority opinions and more dissents. The increase in dissents from Johnson may have been due to influence from Jefferson, who praised the practice and urged Johnson to publish more. Ultimately, Johnson wrote about half of the dissents during the Marshall Court.