To date,  there has been remarkably little legislation around Brexit; the European Union (Notification of Withdrawal) Act 2017 (enacted to authorise the Government to serve the Article 50 notice) is the only piece of legislation that has actually passed into law.  The European Union (Withdrawal) Bill (formerly known as the Great Repeal Bill) (the "Withdrawal Bill") is crawling through Parliament with a record number of amendments and is now not expected to become law until 2019.  The other Brexit-related legislation before Parliament consists of:

• The Taxation (Cross-border Trade) Bill which empowers the Government to impose customs duties on goods imported into the UK, and to impose and regulate value added tax, in each case post-Brexit;
   
• The Trade Bill, which empowers the Government to implement international trade agreements and establishes a Trade Remedies Authority; and
   
• The Sanctions and Anti-Money Laundering Bill (the "Sanctions Bill").

The Sanctions Bill is needed to enable the Government to implement United Nations sanctions regimes and to keep anti-money laundering and counter-terrorist financing measures up to date.  These matters are currently largely dealt with through the European Communities Act 1972, which will be repealed when the UK withdraws from the EU.  At the heart of the Bill is a power for "an appropriate Minister" to make regulations imposing sanctions or relating to anti-money laundering or counter-terrorist financing.  The "appropriate Minister" is the Home Secretary or the Treasury, and the Bill provides that he may make regulations if the appropriate Minister "considers it appropriate" for the purpose of compliance with a UN or other international obligation; or for a purpose he considers would (amongst other things):

• further the prevention of terrorism;
   
• be in the interests of national security, or international peace and security;
   
• promote the resolution of armed conflicts or the protection of civilians in conflict zones or compliance with international humanitarian and human rights law, democracy or the rule of law;
   
• contribute to multilateral efforts to restrict the use of weapons and materials of mass destruction; or
   
• further a foreign policy objective of the UK Government;  

Whilst these are all good things (no one is disputing the importance of protecting national security or protecting human rights) the powers granted are very wide, and are subject only to a subjective requirement that the Minister considers their use "appropriate", rather than necessary.  The UK already has extensive legislation on sanctions, terrorism and money laundering, and the Withdrawal Bill will preserve any such legislation of EU origin in UK law (along with the rest of the acquis).  It is not clear why the Government is seeking to acquire such wide scale additional powers at this stage.  For example, section 16 of the Bill gives the Minister power to create new criminal offences punishable by up to 10 years’ imprisonment, without a vote in Parliament.

What all the Brexit-related draft legislation has in common is heavy reliance on so-called "Henry VIII powers".  These are powers for Ministers to pass laws by subordinate legislation, often without further parliamentary scrutiny.  Parliament is rightly very wary of granting Government extensive Henry VIII powers because of the risk to Parliamentary sovereignty.  The Sanctions Bill started life in the House of Lords, who are particularly protective of Parliament's powers, and their Lordships were distinctly unimpressed with the draft legislation. Lord Judge, a highly regarded former Lord Chief Justice (the head of the judiciary of England and Wales) did not hold back in his comments: at Second Reading he described it as a "bonanza of regulations"; by the time the Bill reached Committee stage, he had concluded "We really should rechristen this Bill the Sanctions and Anti-Money Laundering (Regulation Bulk Buy) Bill".  A Labour peer, Lord McNally, described the Bill as a "constitutional car crash".

The Lords are particularly exercised by what they see as the irony that Brexit, which many claim came about from a desire to restore sovereignty to Parliament, is in fact being used to take power away from Parliament and vest it in the executive.  Whatever the final form of the Sanctions Bill, it is clear that the argument about the way Brexit is being implemented will continue to rage, especially in the Lords.  This is significant, because the Government does not have a majority in the House of Lords, and the Lords are by and large in favour of the EU and the UK remaining in it.  In addition, they are unelected and, unlike MPs, do not face the prospect of having to explain their actions to Leave-voting constituents at the next election.