A reminder that the UK has *already* agreed, after transition, to be tied permanently to EU laws and a role for the EU court. It’s in the Northern Ireland Protocol signed by the current Government.
See
Or, as I said to the HoL EU Select Committee (from my summary of its letter to BEIS at uksala.org/house-of-lords…) 
And as it concluded: -
If the State aid provisions the Govt has *already* signed up to are to be changed, we will need to offer the EU adequate anti-subsidy commitments in return. Claiming that we won’t sign up to any such commitments is not sustainable given what we have *already* agreed.
We are going to have to agree to something “unprecedented”: because we have *already* agreed something unprecedented (the extension of Commission and ECJ jurisdiction to a non Member State).
And see also customs.
We have *already* agreed to apply, in full, the Union Customs Code, under the supervision of the Commission and ECJ, to all imports to Northern Ireland, including from GB. Again, “unprecedented”: but conceded.
These existing commitments will kick in at the end of transition unless we negotiate something else.
Successful renegotiation requires an honest assessment of where we are and an acceptance that a tight deadline is our enemy, when the non-agreement default is not something we want to live with.
