The chairwoman of a committee overseeing an interest-rate benchmark at the centre of a global scandal was forced out of her post after a disagreement over greater independence from the company that runs the process, according to people familiar with the matter.

Joanna Perkins, a financial lawyer who has advised regulators, left the committee in July. The company, London-based Ice Benchmark Administration, a unit of Intercontinental Exchange, at the time gave no explanation for the change.