“Its NOT law to have a TV license.....”
‘Fraid it is nailit. Communications Act, 2003, Section 363:
https://www.legislation.gov.uk/ukpga/2003/21/part/4
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363Licence required for use of TV receiver
(1)A television receiver must not be installed or used unless the installation and use of the receiver is authorised by a licence under this Part.
(2)A person who installs or uses a television receiver in contravention of subsection (1) is guilty of an offence.
(3)A person with a television receiver in his possession or under his control who—
(a)intends to install or use it in contravention of subsection (1), or
(b)knows, or has reasonable grounds for believing, that another person intends to install or use it in contravention of that subsection,
is guilty of an offence.
(4)A person guilty of an offence under this section shall be liable, on summary conviction, to a fine not exceeding level 3 [£1,000] on the standard scale.
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We can argue over the niceties of detection and enforcement, but the statute is plain enough.