“Cuckooing” in the homes of vulnerable people by drug gangs should become a criminal offence, according to a call from the Centre for Social Justice (CSJ) thinktank which has gathered cross-party backing. Labour MP Jess Phillips and the former Conservative leader Iain Duncan Smith are leading calls for the practice – which was spotlighted in the BBC series Happy Valley – to be criminalised as part of an overhaul of the 2015 Modern Slavery Act. Cuckooing is where offenders take over someone’s home and use it for their own purposes, often the storage of drugs or weapons, the CSJ said. Victims are often targeted because they are vulnerable through addiction, age or disability, and offenders can be violent and threatening. During a police crackdown in March 2022 on “county lines” gangs who distribute drugs from city hubs to bases in smaller towns and villages, they visited 799 different cuckooed addresses. Polling by the CSJ has found that one in eight people have seen signs of cuckooing in their communities. North Wales police told the thinktank that of 54 cuckooing victims they had identified between March 2021 and April 2022, 44 were thought to have problems with substance misuse, 10 were disabled or learning disabled, and 39 were unemployed. “We must outlaw this exploitation of vulnerable people, threatened and manipulated by drug gangs who take over their home,” said Phillips, the MP for Birmingham Yardley. “We cannot leave them any longer to suffer behind closed doors at risk of being prosecuted themselves.” Duncan Smith, the MP for Chingford and Woodford Green, said: “It cannot be right that the invasion of someone’s home by gangs for criminal purposes is out of the reach of the Modern Slavery Act. This isn’t a drug crime or a property crime, it is a crime that devastates vulnerable people in the very place that should be their sanctuary.” The proposal to make cuckooing a crime is part of calls to update the law on modern slavery. The CSJ said nearly four times as many modern slavery victims were formally identified and referred for support in 2021 compared with the year the laws were introduced. One rescued victim of cuckooing told the CSJ: “It was the bereavement of my mum; I was taken advantage of. They was feeding me free drugs. ’Cos I was so wasted on what they were giving me I didn’t even see the change until it was too late when people started moving in and then when the prostitution started.” Another survivor said: “It’s scary, your house is taken over, you don’t know who’s knocking on your door. People coming to your door every two minutes looking for them. They’re threatening people in your home, threatening me in my home. It totally takes over your life.” The Crown Prosecution Service says cuckooing can be out of reach of the Modern Slavery Act if the victim has done nothing apart from acquiesce to drugs being supplied from their home. But if they are forced into labour, threatened or attacked, charges could be brought under existing laws. The government announced in May 2022 that it plans a new modern slavery bill to “strengthen the protection and support for victims of human trafficking and modern slavery and increase the accountability of companies and other organisations to drive out modern slavery from their supply chains”. However, it did not mention addressing cuckooing. A Home Office spokesperson said: “Cuckooing is wholly unacceptable and the government is determined to tackle it and those who perpetrate this abuse. There are a range of tools that can be applied to disrupt this behaviour which can result in criminal sanctions if breached.” It said police had closed down more than 2,900 lines, made more than 8,000 arrests, and engaged more than 9,500 people through safeguarding interventions.