A Tory MP has failed in a bid to change to the law to allow only English MPs to amend legislation that solely affects England.
Harriet Baldwin's Legislation (Territorial Extent) Bill would require draft government legislation to clearly specify how it affects each of England, Scotland, Wales and Northern Ireland. MPs from all parts of the UK would be able to vote at second and third reading on England-only bills, but not amend them.
The bill is designed to address the West Lothian Question - the issue of whether MPs should vote on issues which do not directly affect their own constituents as a result of devolution.
But Labour blasted the bill as "extremely badly drafted" and "ill-conceived" as it was debated at report stage on 8 September 2011, accusing Mrs Baldwin of trying to bring in her own agenda "via the back door".
Shadow justice minister Helen Goodman told the Commons: "[Mrs Baldwin's] underlying concern is clearly that people are taking views on legislation that affects part of the UK which are beyond part of the UK which their constituency is in.
"If that was her concern she should have presented a bill which made that case. She has presented a different bill and as I say it is a flawed bill."
Labour backbencher Dawn Purvis said the bill "undermines the principle that all members of the House are equal".
While Mark Lazarowicz, Labour MP for Edinburgh North and Leith, warned it could create "two kinds of members in this House".
Tory Oliver Heald dismissed this idea saying that every parliamentarian was elected to the Commons on the same basis.
Fellow Tory, Iain Stewart, warned that the Union was at risk because of growing English resentment towards MPs from devolved nations being able to vote on English matters, when English MPs cannot vote on the same issues in Scotland, Wales and Northern Ireland.
"It is not a crisis point at the minute", he said. "But bit by bit it is growing and, if we leave it unchecked, at some point in the future we will be in very difficult waters and the Union will be under threat."
SNP MP Pete Wishart told MPs that as long as the Union existed there would be no answer to the West Lothian Question.
Appealing to the House to support her bill Mrs Baldwin said it was "the only vehicle available to colleagues who might want to see this great constitutional issue addressed".
But Constitutional Reform Minister Mark Harper urged her to withdraw the bill.
He stressed that the government was committed to resolving the issue, referring to the West Lothian Commission announced on Thursday.
Mrs Baldwin decided to push her bill to a vote, but MPs decided by 40 votes to 24 not to give it a third reading.