A challenge to the Government's controversial move to cut housing benefit failed today at the High Court.
In July, Mr Justice Supperstone was told that changes brought in earlier this year, which the Child Poverty Action Group (CPAG) likened to "social cleansing", could force thousands of poorer people out of accommodation in expensive areas, particularly in central London.
Ministers say that, without reform, expenditure on housing benefit would reach £24.7 billion by 2014/15 and that the new measures, amounting to £2.4 billion in savings, are necessary.
The judicial review brought by the CPAG challenged the legality of national caps imposed on the amount of local housing allowance (LHA) for accommodation of a given size.
The caps mean that LHA weekly rates cannot exceed £250 for a one-bedroom property, £290 for two bedrooms, £340 for three bedrooms and £400 for four bedrooms.
Martin Westgate QC claimed the Secretary of State for Work and Pensions had acted outside powers conferred by the 1996 Housing Act when read with the 1992 Social Security Contributions and Benefits Act, and failed to comply with his duties under equality legislation.
Referring to a report from the New Policy Institute which showed that large families were roughly twice as likely to be ethnic minority households, he said the caps would have a disproportionate impact on them.
Dismissing the case in London, the judge said it was clear that the minister was well aware of his equality duties, paid specific regard to them and had carried out two equality impact assessments before reaching a decision.
He did not accept that the minister should have concluded that the measures were "likely" to impact on ethnic minority groups disproportionately.
Rather, he was entitled on the basis of the information available to conclude that they "may" have such an impact.
The judge said: "I am satisfied that the information gathered and considered by the defendant was adequate for the purposes of performing his statutory duty."
He commented that the weight to be given to the countervailing factors was a matter for the minister and it could not be argued that the regard he paid to them was unreasonable or perverse.
The measures were implemented in light of what the Government's lawyers described as "the strong socio-economic imperatives in play", he added.
Later, Work and Pensions Secretary Iain Duncan Smith said: "CPAG's challenge to our housing benefit reforms was an ill-judged PR stunt, and amounts to nothing more than a massive waste of taxpayers' money and court time.
"The cost of housing benefit has spiralled completely out of control, and this judgment is further vindication that our reforms will ensure support is in place for those who need it, but stop the crazy excesses we have seen in recent years of people on benefits living in houses that those in work could not afford.
"I sincerely hope CPAG will think twice before repeating this ridiculous and irresponsible behaviour in future."
CPAG chief executive Alison Garnham said: "We are greatly disappointed at today's judgment. Minority ethnic and lone parent families are already at higher risks of child poverty and the cuts to housing benefit that we challenged will make this situation even worse, driving people out of their homes and disrupting children's education.
"The bad news for poor families is piling up this week, following the stark warning from the Institute for Fiscal Studies that hundreds of thousands more children will fall into poverty because of the Government's welfare reforms.
"We will now be studying the decision before deciding on our next steps. We will continue opposing the cuts and campaigning for fairness and justice for the families who are bearing the brunt of a financial crisis that they were not responsible for."