Is Suella’s migration plan legal?

A typically robust performance by Suella Braverman on Radio 4 this morning. The Home Secretary defended her plans to clamp down on small boat crossings, telling the Today programme that

We are within the boundaries of the law but we are trying new arguments, we are testing novel interpretations of the law. But we do not consider that we have crossed that boundary and we do not consider that we are in unlawful territory — we very strongly view our proposals as lawful.

How exactly does that square then with, er, the introduction to her flagship legislation which begins thus:

I am unable to make a statement that, in my view, the provisions of the Illegal Migration Bill are compatible with the Convention rights, but the government nevertheless wishes the House to proceed with the Bill.

In a letter to MPs and peers, Braverman has said that she had had to make a statement under the Human Rights Act, which enshrined the convention rights in the UK:

This does not mean that the provisions in the Bill are incompatible with the convention rights, only that there is a more (than) 50 per cent chance that they may not be.