Nairobi, July 21 -- For more than two decades, close to 200 bank customers believed the courts would one day order banks to refund millions of shillings they say were unlawfully charged on their loans.

Many had taken mortgages and business loans years earlier, only to watch their debts balloon after banks increased interest rates and other charges.

They insisted that the increases were illegal because they had not received the Minister for Finance's approval, as required by the Banking Act then in force.

Some lost property. Others spent years repaying loans they believed had been inflated by unlawful charges. Together, they turned to the courts in what became one of Kenya's longest-running banking disputes.

The case was initially file...