have a thumb on the scale

== English == === Alternative forms === thumb on the scales === Etymology === An allusion to a butcher who cheats customers by surreptitiously using a thumb to apply extra pressure to the scale when weighing meat to calculate the price of a sale. === Pronunciation === === Noun === thumb on the scale (usually uncountable, plural thumbs on the scale or thumbs on the scales) (idiomatic) An act of bias or a tactic for cheating which creates a situation that unfairly benefits one party involved in an interaction. ==== See also ==== tip the scales