Only because the BBC has a special place in the law:
> In 1991, the BBC assumed the role of TV Licensing Authority with responsibility for the collection and enforcement of the licence fee.[5] The BBC is authorised by the Communications Act 2003 to collect and enforce the TV licence fee. Section 363 of the Act makes it against the law to install or use a television receiver to watch or record any television programmes as they’re being broadcast without a TV Licence. Section 365 of the same Act requires the payment of the TV Licence fee to the BBC.
That hardly makes the case the BBC is Fully Independent from the British Government, which is what is being discussed here.
> In 1991, the BBC assumed the role of TV Licensing Authority with responsibility for the collection and enforcement of the licence fee.[5] The BBC is authorised by the Communications Act 2003 to collect and enforce the TV licence fee. Section 363 of the Act makes it against the law to install or use a television receiver to watch or record any television programmes as they’re being broadcast without a TV Licence. Section 365 of the same Act requires the payment of the TV Licence fee to the BBC.
That hardly makes the case the BBC is Fully Independent from the British Government, which is what is being discussed here.