A landlord turned a "blind eye" to victims of a modern slavery gang being housed in his properties in squalid conditions, police say.
Kashmir Singh Binning, 40, leased three Birmingham properties to a gang who forced up to 400 Polish people to work.
Det Sgt Mike Wright, of West Midlands Police, said Mr Binning's role "was pivotal" to the gang being able to house victims easily and affordably.
The force said a "landmark" ruling had now placed conditions on his tenancies.
Members of the gang, who were behind the biggest modern-day slavery network exposed in the UK, were jailed in July 2019.
No cash payments
A judge at Birmingham Magistrates' Court granted a Slavery and Trafficking Risk Order against Mr Binning on Friday.
The five-year order binds him by various conditions, including that he cannot accept cash payments from tenants and must provide the local authority with signed tenancy agreements with occupants' details.
The order was "the first of its kind ever secured under modern slavery legislation", the force said.
Police said he was also ordered to pay £14,000 court costs.
Officers said they advised Mr Binning, of Kirkham Way, Tipton, his three properties were being used to house slavery victims in August 2016.
But he continued to rent out them out, getting £135 a week for each address.
His phone records showed messages between him and the traffickers, including Ignacy Brzezinski who, helped run the network, "whom he considered a friend".
Det Sgt Wright said: "He was friends with some of the suspects and willing to turn a blind eye.
"He claimed he had no idea people housed in his properties were being exploited… but all the evidence suggested otherwise."
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