Editorial: The Tories needed to get such a key appointment as BBC chair right, yet now a shadow is cast over the man who was chosen

​​The appointment of Richard Sharp as BBC chairman has cast yet another retrospective shadow on the premiership of Boris Johnson.

Mr Sharp is found by a committee of MPs to have made "significant errors of judgement" acting as a go-between on a loan for Mr Johnson, while applying for the post. While Mr Sharp says he did not help arrange a guarantee on the loan, it is plain that his role in this £800,000 loan should have been disclosed.

To say that this is an important matter is not to join hyper-critical attacks on the former prime minister, but rather to say that this was an obviously relevant factor. Mr Sharp was benefiting from one of the most significant prime ministerial powers, personally appointing people to positions of influence.

Mr Johnson would inevitably be deeply grateful to Mr Sharp for his part in securing such a large loan.

The Westminster culture committee is right to step back from calling for Mr Sharp to quit. We have more than enough assaults on the ability of prime ministers to be able to use the powers that they rightly have. But there has to be trust for such a system to work. Mr Johnson's premiership has been plagued with the whiff of cronyism, from freebies for the PM to Covid contracts to ministerial appointments flagrantly based on loyalty to him rather than on talent.

The situation with Mr Sharp is all the more deplorable given the need for serious reform at the BBC with regard to bias. While much of the corporation's broadcasting output has always been of a very high calibre, there is institutional political bias, including serious failings with regard to coverage of Northern Ireland.

The director-general Tim Davie seems aware of how toxic it is for there to be widespread perceptions of bias in the UK national broadcaster. The BBC chairmanship is an appointment the Tories needed to get right.