The Lords’ Constitution Committee rushed out a report on the last day of Parliament to provide the only clause-by-clause scrutiny of the Prime Minister’s EU withdrawal legislation.

Boris Johnson’s plan to avoid public scrutiny of his EU withdrawal bill has been torpedoed by peers in a forensic report revealing a new power grab by ministers looking to change fundamental laws without proper debate in Parliament.

Peers on the House of Lords Constitution Committee rushed out an interim report on the last day of Parliament to provide the only clause-by-clause scrutiny of the legislation – after the Prime Minister chose to dissolve Parliament to have a General Election, rather than face proper scrutiny of the measure in the Commons.

The report draws attention to the ramping up of the so-called Henry VIII powers under the Northern Ireland protocol to allow ministers to change or repeal laws without parliamentary legislation.

It also points out that there is no provision in the law for any consultation procedures with the Scottish Parliament, the Welsh Assembly or the Northern Ireland Assembly during negotiations with the EU for a new trade deal. Each body will simply be informed about the progress of the negotiations.

The report also confirms Labour’s fears that workers’ rights are not well protected, as human rights, in the withdrawal bill. It questions whether the Good Friday Agreement will be properly respected under the new plan to move the trade border to between Great Britain and Northern Ireland.

It highlights new rules allowing ministers to alter criminal sentences and change charges by any public body without a debate in Parliament – unless MPs and peers spot the change and demand a debate. It also states that the arrangements for the new trade border in the Irish sea are only skeletal and need fleshing out before the bill becomes law.

The new power grab by ministers seems to be centred mainly on Northern Ireland. While in Great Britain there are restrictions on what can amended using Henry VIII powers, this does not apply to Northern Ireland under a new protocol.

The report states: “There is no restriction on… powers being used to impose or increase taxation or fees, make retrospective provision, create a relevant criminal offence (i.e. with a penalty exceeding two years imprisonment), establish a public authority, amend, repeal or revoke the Human Rights Act 1998 or any subordinate legislation made under it, or amend or repeal the Scotland Act 1998, the Government of Wales Act 2006 or the Northern Ireland Act 1998.”

The peers add: “It would require the strongest of justifications for ministers to be given a broad power by regulations to alter as they think ‘appropriate’ any existing law, including the Act providing the power, on the basis of the terms of the withdrawal agreement.”

On worker’s rights, it draws a distinction between the protection of human rights – which can be backed up by the courts – and workers’ rights.

“The scheme in this bill is also different insofar as that in the Human Rights Act 1998 is in the context of the UK’s continuing obligations under the ECHR and accountability to UK courts and the European Court of Human Rights for departures from such obligations,” the report states. “Under the bill, by contrast, there is, at present, no planned international treaty arrangement protecting such workers’ rights in the UK after the implementation period completion date.”

On Northern Ireland, it takes up the issue raised by the Democratic Unionist Party that the arrangements for Northern Ireland to continue in both the EU single market while belonging to the UK customs area, long after Great Britain has left the EU, would be subject to consent of the people.

Baroness Taylor of Bolton, chair of the committee said: “We decided to get this out without comment before Parliament rose. It is an analysis rather than a critique.”