https://www.theguardian.com/technology/2019/oct/04/facebook-exempts-political-ads-ban-making-false-claims

Firm quietly rescinds policy banning false advertising as UK general election looms

Facebook has quietly rescinded a policy banning false claims in advertising, creating a specific exemption that leaves political adverts unconstrained regarding how they could mislead or deceive, as a potential general election looms in the UK.