The Home Office doesn’t know how many landlords are failing to carry out controversial checks on potential tenants. Photograph: Alamy Stock Photo

One year ago, on 1 February 2016, the government implemented its “right to rent” scheme, requiring landlords who let property in England to carry out checks on the immigration status of potential tenants, as part of a government drive to create a “hostile environment for illegal migrants”.

The government plans to extend the scheme to the rest of the UK. But before it does, the government must ask whether the scheme’s biggest effect has been to deny some of society’s most vulnerable people the accommodation they need.

Right to rent document checks have to be completed by private landlords, as well as some housing associations and, in theory, by anyone taking in a lodger. When the government launched the scheme (pdf) last February, it was estimated that more than 2.6m checks could be needed every year.

The problem is that no one knows whether this is happening. The Home Office has admitted it cannot monitor the scheme and it’s a fair bet given the limited publicity that at least a proportion of England’s 1.8m private landlords are still completely unaware of it.

That isn’t the only thing that goes unmonitored. Even more concerning is the effect on the attitudes of landlords of new criminal penalties for not complying with the scheme – especially when they are faced with applicants who, through no fault of theirs, haven’t got straightforward documents like a British passport.

The organisations we work with, including housing advice agencies and migrant advisory bodies, tell us that many people are now finding it much more difficult to rent a flat. Refugees who have been accepted in the UK often have to wait many weeks for documents to prove it – and many become homeless because they can’t get either a social or a private tenancy.

People who are refused asylum may need to reopen their case if they get legal representation, and need somewhere stable to live while this is resolved. But the projects that traditionally help them now fear falling foul of the law.

Housing Justice, a national charity that supports local groups and churches to house homeless people, is just one organisation that has told us they are seriously concerned that right to rent could act as a barrier to their work.

Meanwhile British people can also be affected if they have no passport or other accepted proof of UK residence, and there are a raft of other circumstances that could mean a person may not satisfy the checks.

Landlord bodies admitted from the start of the scheme that it would lead to more discrimination: but we simply don’t know how much – especially as those affected are unlikely to make formal complaints and discrimination in housing is notoriously difficult to prove.

At the moment, British and other EU nationals have an automatic right to rent provided they can show their documentation. But after Brexit, rules for the 3 million EU nationals still in the UK are likely to change, potentially making the checks even more complicated.

Is it really worth putting landlords, tenants and agents through the time and cost of an estimated 11,300 daily checks?

Up to December 2016, the scheme identified only 654 undocumented individuals living in private rented accommodation. That means more than 4,000 checks for every individual identified. The additional work by landlords was estimated by the government to cost a staggering £4.7m a year.

The Home Office points to the deterrent effect of the scheme but, without proper monitoring, it has no means of knowing how many undocumented migrants are refused tenancies, or how many legitimate applicants are turned away before they can prove their right to rent. It doesn’t even know how many landlords are failing to carry out the checks.

It’s time for the government to seriously reconsider the impact of right to rent on vulnerable tenants and would-be tenants before it is rolled out to Scotland, Wales and Northern Ireland.

It is simply not good enough to claim that the scheme has a deterrent effect when the proven benefits are so limited and there are regular reports of the damage being caused.

Original post and comments: Guardian Housing Network