Bad landlords and letting agents convicted of exploiting tenants in London face public naming and shaming online.

The city’s mayor Sadiq Khan will start the campaign to improve housing standards with an online database allowing tenants to check out their new landlords.

Six councils in the capital will join the scheme in the autumn – Brent, Camden, Kingston, Newham, Southwark and Sutton. The rest of London’s 40 council will follow during 2018.

“I refuse to stand by as thousands of Londoners suffer sky-high rents and horrendous living conditions,” said Khan.

“I have seen first-hand the abysmal conditions that some private renters are forced to endure.

“Most landlords treat renters well, but a minority are exploiting their tenants and it’s simply unacceptable.”

The database will let renters check if a landlord or letting agent has a criminal conviction related to housing offences.

Last year, 410 landlords were reportedly prosecuted in London. Most of the allegations related to licensing and maintaining proper health and safety standards in houses of multiple occupation (HMO).

Seven out of 10 prosecutions in the capital were in Newham, where a borough-wide licensing scheme for all buy-to-lets is operated by the council.

The London mayor’s measure seems to duplicate a database already announced by outgoing Housing Minister Gavin Barwell.

The Housing and Planning Act 2016 to tackle rogue landlords includes a database of landlords and property agents convicted of housing offences.

One factor leading to a national bad landlord database is that with hundreds of councils responsible for granting HMO licences, checking if a landlord is a fit and proper person is almost impossible as no central record of convictions is maintained.

With the latest HMRC figure based on tax returns putting the number of UK landlords at 1.75 million and fewer than 1,000 a year facing courts, that makes the percentage of bad landlords at just 0.05% of the total.