Tim Farron Lib Dems
Tim Farron, leader of the Lib Dems, said his party's peers will use the House of Lords to try to block elements of the housing and planning billGetty

Liberal Democrats say they will use the House of Lords to try to block a number of measures in the government's controversial Housing and Planning Bill, which the party leader Tim Farron claimed is "riddled with holes and unfairness". The bill will soon enter the House of Lords for its final stages before, if passed, coming into law.

It is a radical overhaul of the housing system in England and Wales intended to increase home ownership and reduce the government's welfare spending. Among its most contentious changes are the abolition of lifetime tenancies in council-owned homes, the "right to rent" immigration checks by landlords, so-called "pay to stay" which will see higher-earning social tenants made to pay market rents, and the extension of right to buy to housing associations.

There is also an obligation on councils to ensure "starter homes" -- discounted properties for first-time buyers aged under 40 to help them onto the property ladder -- are built in their local areas. Starter homes would be counted in developers' quotas for affordable homes, which they must include in housing projects to secure planning consent, or pay a fee to the council to wave. The government's critics say this will lead to fewer homes available at an affordable rent for those who cannot pay market rates.

"The housing bill is riddled with holes and unfairness," Farron said. "The government has clearly drafted a bill without consulting anyone who has lived in or experienced the realities of social housing. Social housing is a lifeline for thousands of people and the Conservatives seem driven by ideological dogma to sell off these homes. The prime minister used to be vocal in his support for social housing. His actions show now that he was merely paying lip service."

A Department for Communities and Local Government (DCLG) spokesman said more council housing has been built since 2010 than in the previous 13 years "and we also recently announced the intention that two additional affordable homes will be delivered to replace each high-value vacant home sold in London. Our landmark housing bill is delivering the new homes needed whilst ensuring that we make the best use of social housing based on need and income."

The Lib Dems have only eight MPs in the House of Commons after a disastrous 2015 general election, prior to which they were in a coalition government with the Conservatives. But in the House of Lords there are 109 Lib Dem peers. Labour has 213 peers, while there are 178 crossbenchers, 26 bishops, and 41 from other parties or non-affiliated. The Conservatives have 250 peers, giving the Lib Dems -- if they can rally support from Labour peers and others -- a fighting chance of blocking parts of the housing bill.

Towards the end of 2015, the House of Lords voted down government plans to cut working tax credits in a move Chancellor George Osborne said raised "constitutional issues" because "unelected Labour and Lib Dem lords" had defied the will of MPs in the House of Commons.

But the Commons retains ultimate power. The Parliament Act 1911 removed the Lords' power to veto a bill. A further Parliament Act in 1949 diluted the Lords' power further by allowing them to delay a bill only by a year at most. If the Lords rejects a bill, it goes back to the Commons, usually with amendments, for discussion. If MPs vote down the amendments, and continue to support the original bill when it is reintroduced by the government, it will pass directly to the queen for royal assent and so become law without needing formal approval from the Lords.