Tenants with one spare bedroom have had a payment reduction of 14% and those deemed to have two or more spare a reduction of 25%.
Lawyers for the 10 cases say that, unless the families move from their homes into smaller properties, they face building up rent arrears and being forced out any way.
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Craig Johnson, 25, was driving with partner Julie Douglas and their one-year-old daughter Maisie when the rock was hurled at them.
A terminally ill five-year-old boy led out the England team at Wembley with his "best friend" Jermain Defoe.
It comes as the country faces a major migrant crisis with more than 62,000 stranded including outside the port of Piraeus.