As the government faces a two-day debate on proposed changes to the House of Lords, we look at why the plans are being met with such fierce opposition and two opposing MPs debate the issues.
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What changes to the House of Lords is the government proposing?
The government wants 80 per cent of peers in the house of Lords to be elected. It also wants to cut the number of peers by almost half to 450. Heriditary peers would be replaced with elected members who would be able to serve 15 years, instead of the current system which allows peers to be lifetime members.
The remaining 20 per cent, or 90 peers, would include 12 Church of England bishops and 78 appointed peers. A commission would be set up to ensure peers were not appointed on party lines.
Why does the government want to make these changes?
The government is pushing for the reforms because it says the current unelected chamber is not democratic. Deputy Prime Minister Nick Clegg is opening the two-day debate on the reforms. Mr Clegg has urged David Cameron to persuade Tory rebels to back the government motion, calling it a "test of David Cameron's leadership".
What are opponents of the reforms saying?
Around 70 Conservative MPs have signed a letter opposing the changes. They argue that constitutional change should not be the government's priority during a recession and say the proposals threaten to "pile a constitutional crisis on top of an economic crisis". They also want the bill to undergo "full and unrestricted" scrutiny, saying they need more time than the 10 days allocated by the government.
Others say the system works well now, so there is no need to change the way the Lords operates. They argue that the new chamber would be "less expert" and more expensive than the current set-up.
MPs also argue that the proposed reforms would change the balance of power and potentially undermine the way the House of Commons operates.
Is the bill likely to be passed?
The government will struggle to get the bill through due to mounting opposition from Conservative MPs and Labour politicians. Up to 100 Tories are set to oppose the vote on the timetable for the bill, which would lead to the government's first significant defeat. The Lib Dems believe that without a programme motion - which limits the amount of time the bill can be debated- the bill would be killed off to ensure it does not take over the government's parliamentary schedule.
How could this affect the coalition?
The proposed changes to the House of Lords has already caused divisions in the coalition. Some Tories have accused Mr Clegg's party of "blackmail" after one of his senior aides said the Lib Dems would block parliamentary boundary changes in retaliation if Conservative MPs voted against the bill.
Nick Clegg has also warned that the coalition would be heading into "uncharted territory" if the bill was defeated.