A group of peers is amassing a "fighting fund" to sue the Government if ministers use the Parliament Act to implement its legislation abolishing the voting rights of those with inherited titles. The plan could delay the removal of the hereditary peers by up to five years, even if the legal challenge is eventually defeated.
The Government has warned that it will use the Act to force through the proposals after a year, even if they are rejected by the House of Lords. However, peers have been advised by constitutional lawyers that the Act is open to challenge on the grounds that it was illegally forced through Parliament in 1949.
Lord Kingsland, the shadow Lord Chancellor and himself a constitutional lawyer, is among the peers discussing the plan to use a legal technicality to save a hereditary element in the Lords.
Although this is not official Conservative policy, it has won wide support on the Tory benches. "There is certainly a question mark over the legal position of the Parliament Act," a senior Tory source said. Another peer added: "There is a powerful revolt brewing."
The peers are being advised by Michael Shrimpton QC, a barrister who specialises in constitutional law. He said that in his opinion the Parliament Act, passed in 1949, was "null and void" because it had been forced through despite opposition from the Lords.
"The Parliament Act was never approved by the House of Lords," he said. "If the Government used this to force its proposals through, that would be illegal. Then the question would arise: if it's illegal, how would the Government stop the hereditary peers voting?"
The peers are threatening to challenge the Government in the High Court. If they won their case and ministers appealed, this could lead to the House of Lords itself sitting in judgment on the matter, as the highest judicial body in the land.
Mr Shrimpton believes that in such an extraordinary constitutional case the whole House would have a right to assess the case, rather than just the elite corps of law lords.
Lord Pearson of Rannoch, a Tory life peer, said he had "grave doubts as to whether one House of Parliament is empowered to radically alter the composition of the other without the specific consent of the British people".
Lord Stoddart of Swindon, a Labour life peer, is also aware of the proposal. "If the Government has to use the Parliament Act, then I think it may well be that a number of peers will take it to the courts," he said.
"One part of Parliament cannot amend the composition of another part of Parliament ... I believe if you are going to have reform, it should be fundamental reform."