Freedom from EU law is anything but guaranteed. Article Four of the Withdrawal Agreement gives EU law supremacy over domestic law in a number of areas in respect of the entire Withdrawal Agreement and not just for citizens’ rights, as a House of Lords briefing paper and a senior MP have made clear. Article Four, which provides for direct effect and supremacy, is not limited to the transition period but will continue to apply to those provisions of the Withdrawal Agreement (and of EU law to which the Agreement refers) once the UK has left the EU at the end of the transition period. Thus the status of EU law in the UK at the end of the transition is not clear.
This is just one example of the uncertainty that awaits the UK if the Withdrawal Agreement is accepted, even with modifications to the backstop. A careful reading of its near 600 pages would discover more. Why accept it? Even the Prime Minister can find no reason better than that is the only deal, so that the other options are, she says, no Brexit or leaving without a deal. In fact, no Brexit is not an option: the people voted clearly in 2016 and Parliament has legislated for the UK to leave the EU on March 29, 2019.
But leaving without a deal simply means leaving without agreeing to the special terms that the EU wishes to impose, but following the legal agreements which the UK has made. It leaves open, not just the certainty of being able to trade, as we already do very successfully with most of the world, on WTO rules, and the opportunity to sign free trade agreements globally and reaching a Canada Plus style trade deal with the EU. Indeed, the UK will probably be in a much better position to negotiate an ambitious long-term trade deal with the EU if it leaves cleanly, without the baggage that any sort of divorce deal will inevitably impose.