ex officio

That friend, […] added, with a smile, that he had more than once amused himself with the thought of a verbarian Attorney-General, authorized to bring informations ex officio against the writer or editor of any work in extensive circulation, who, after due notice issued, should persevere in misusing a word.

1830, S[amuel] T[aylor] Coleridge, “Concerning the Right Idea of the Constitution”, in On the Constitution of the Church and State, according to the Idea of Each: […], London: Hurst, Chance, and Co., →OCLC, footnote *, page 19

In the South every negro preacher is ex officio a D.D., and is commonly addressed as Doctor. This enables white Southerners to show a decent respect for his sacred office, and yet avoid the solecism of calling him Mister.

[1921 [1919], H. L. Mencken, chapter 20, in The American Language, 2nd edition, New York: Alfred A. Knopf, →ISBN, →OCLC, footnote, page 138

Meanwhile, to Samsonov’s annoyance, Colonel Knox had arrived in Ostrolenka. Why, nobody knew—probably just to convey the goodwill of the British, who would not themselves be landing on the Continent for another six months. Samsonov disliked those artificial, ex officio European smiles at the best of times, and this visitor would be a hindrance and a distraction just at present.

1989, Aleksandr Solzhenitsyn, translated by H. T. Willetts, August 1914, Farrar, Straus and Giroux, →ISBN, page 136