Born in 1757, in London, England, Kilty studied medicine under Edward Johnson, of Annapolis, Maryland. In the American Revolutionary War, Kilty served in the 5th Maryland Regiment as a Surgeon's Mate from April 1778 to April 1780, when he was promoted to become Surgeon of the Regiment. Kilty was taken prisoner at the Battle of Camden, returning to Annapolis in the spring of 1781. He thereafter attended College of St. Omer in France, then read law to enter the bar. While working as an attorney, Kilty was among the writers of numerous essays condemning the anarchic state of affairs under the Articles of Confederation, which governed until the ratification of the Constitution of the United States in 1787. He was appointed compiler of the laws of Maryland from 1798 to 1800. He published the two volumes known as "Kilty's Laws", then settled in Washington, D.C., in 1800.
Upon the death of Kilty's predecessor, Alexander Contee Hanson, the Governor of Maryland had first offered the vacancy in the office of Chancellor of Maryland to Gabriel Duvall, who declined, and then to Robert Smith, the acting Attorney General of the United States, who also declined. Kilty was then appointed, and he accepted, taking his seat on January 26, 1806. His opinions as Chancellor were noted to be "generally very concise, not laden with citations of authorities like Bland's, but showing close familiarity with English equity jurisprudence". His most important work as Chancellor was his 1811 report on the British Statutes in force in Maryland. The work received high commendation from the Court of Appeals and the profession generally. In Dashiell vs. Attorney-General, 5 H. & J., 403, the court said that "the book was compiled, printed and distributed under the sanction of the State for the use of its officers and is a safe guide in exploring an otherwise very dubious path". Kilty also undertook other public activities during his Chancellorship. In 1807, he was appointed to a committee of prominent citizens to address a British blockade of American vessels; and in January 1808 he assisted in drafting a resolution further condemning British actions against U.S. shipping. Kilty held that office until his death on October 10, 1821, in Annapolis. A memorial was held on October 11, 1821 in the Baltimore County Court, and the National Intelligencer for October 17, 1821, reported an account of the action of the Bar of the District of Columbia on the death of Kilty. Kilty was succeeded in office by John Johnson Sr..
