Councils who employed foreign workers illegally will not face prosecution – despite private businesses being fined up to £10,000 for the same thing.

Across the West Midlands 16 immigrants were found working at four councils without the correct documentation. But while private firms face fines of up to £10,000 for employing foreigners with no right to work in the UK, regional councils have never faced charges, it was confirmed today.

Wolverhampton City Council admitted employing six foreign workers illegally between 2006 and 2009, as did Birmingham City Council.

Staffordshire County Council employed one and Walsall Council employed three.

The staff on Wolverhampton Council’s payroll included a 37-year-old South African computer operator, a 36-year-old bin collector, a 43-year-old clerical assistant, a 28-year-old

Zimbabwean specialist support worker, a 30-year-old Zimbabwean care assistant and a 33-year-old cleaner. All were either dismissed or resigned after disciplinary proceedings began.

Another 48-year-old Zimbabwean worked as a rehabilitation assistant and produced the right documents when disciplinary proceedings started.

But the UK Border Agency today said it had “insufficient information” to prosecute despite councils having owned up to their mistakes to the independent Audit Commission.

Instead they will just receive a reminder about immigration rules.

The agency said local immigration teams would be in contact with councils to ensure they had adequate pre-employment procedures in place.

Two businessmen in Wolverhampton, who were both fined but successfully appealed against the UK Border Agency, today said the rules should apply to councils as well.

Mohinder Atwal of Big Time Soft Drinks and Sotal Sandhu of Sandhu’s Supermarket were each hit with big fines after raids on their businesses last year. But they both appealed and won.