Four families have launched a legal challenge against the government’s benefit cap on the grounds it is ‘discriminatory and unreasonable’.

The families have issued judicial review proceedings against the work and pensions secretary Iain Duncan Smith today at London’s High Court.

Under the policy, which has been applied since 15 April in four boroughs including Haringey where one of the families lives, the government has capped total household benefits at £500 a week for couples and lone parents, and £350 a week for single adults.

The government plans to roll the cap out across the rest of the country from 30 September.

The eight claimants – one parent and one child from each family – will challenge Part 8A of the Housing Benefit Regulations 2006 which was inserted as part of the welfare reform act last year.

They will argue that the regulations are discriminatory and unreasonable. In addition, they will argue that the secretary of state did not take into account the impact of the policy on women, children, the disabled, racial and religious minorities, and carers when formulating the policy.

Hopkin Murray Beskine, the law firm representing the families, said that two of the families are expected to immediately fall into rent arrears and face eviction and street homelessness.

This is because their rent exceeds £500 a week.

HMB added that two of the families have fled domestic violence in circumstances where they were financially reliant upon their abusive partners and now risk losing their homes.

The families have not been named because two of the women are at risk of violence from their ex-husbands.

The claims are supported by charity Women’s Aid which has submitted witness evidence.

Rebekah Carrier, solicitor at HMB said: ‘This is a cruel and misguided policy.  It will have a catastrophic impact on our clients and many thousands more vulnerable children and adults.  They face street homelessness and starvation. 

‘A year ago the Children’s Commissioner warned the government that these changes would result in a sharp increase in child poverty and homelessness, with a disproportionate impact upon disabled children and children of disabled parents, and some BME groups. The difficulties now faced by my clients were predictable and avoidable.’