Before he was made UK business secretary this week, Jacob Rees-Mogg’s Cabinet Office job was to identify Brexit opportunities and improve government efficiency, which he identified as an opportunity to leave notes on the empty desks of civil servants he felt should not be working from home.

But one of the final decisions he made in his old job, which also included running government procurement, was one of the most interesting. And it had nothing to do with the UK leaving the EU.

Counter-intuitively, Rees-Mogg — the red-tape-slashing, true-blue, small-state Tory — decided to blackball Bain & Company, the US management consultancy that won £40mn of contracts from the Cabinet Office for Brexit-related work.

Bain found itself in hot water recently over the South African “state capture” scandal: the systematic plundering of state entities, presided over by the then president Jacob Zuma but facilitated by some of the world’s best-known companies. Two South African commissions have found Bain helped hobble the country’s formerly esteemed revenue service.

Rees-Mogg barred Bain from UK government contracts for three years on the basis that it was “guilty of grave professional misconduct which renders its integrity questionable”. Last week, Bain duly filed a legal challenge, arguing that his decision was based on a flawed process.

It was certainly a punchy decision by Rees-Mogg that should be worrying for companies caught up in scandals, anywhere in the…