Taxation (Cross-border Trade) Act 2018
Would require a parliamentary majority to overturn this law. The Conservatives don't have that majority. So even if what dribbles says was completely true, its obsolete anyway.55 Single United Kingdom customs territory
(1)It shall be unlawful for Her Majesty’s Government to enter into arrangements under which Northern Ireland forms part of a separate customs territory to Great Britain.
(2)For the purposes of this section “customs territory” shall have the same meaning as in the General Agreement on Tariffs and Trade 1947 as amended.