This week Donald Trump complained that the congressional inquiry into his possible impeachment was a “lynching”, being conducted “without due process or fairness or any legal rights”. Observers, rightfully disgusted, quickly pointed out the word’s long association with racist murders of African Americans in the south. Yet its origins – in the midst of the American war of independence – remain disputed.

The first known printed use of “lynch law”, in 1811, refers to one Captain William Lynch of Virginia, who in 1780 formed the “Pittsylvania County alliance”: a local tribunal independent of the established legal system. The OED accepts this as the origin of “lynch law” to mean punishment by “a self-constituted court armed with no legal authority”. In the view of the American National Biography, on the other hand, the term is owed to another Virginian, Charles Lynch, who imprisoned loyalists in the county jail under what he later called “Lynch’s law”.

Whatever its origin as a name for ad hoc tribunals in turbulent times, “lynching” later came to mean exclusively summary killing. Luckily for Trump, this is something that, as a white American, he has little cause to fear.

• Steven Poole’s A Word for Every Day of the Year is published by Quercus.