Despite an Appeal Court decision which states clearly that consumers should not be made to pay exorbitant interest after a debt has been paid, there are some debt collectors who still charge huge amounts to clients.

Tinto Incorporated Attorneys are accused of charging a debtor four times more than the amount of the loan she took, which is in contravention of the in duplum rule.

The in duplum rule is a common law that protects consumers from exploitation by ensuring that their creditors cannot allow interest to accumulate indefinitely.

Take the case of Regina Thoane of Rustenburg, North West, who signed as surety on a student loan taken by her sister in 2010.

Thoane said when she signed as surety, her understanding was that her sister would repay the loan once she completed her studies and began to work.

Because their pensioned mother could not afford tertiary fees for her sister Nthati Makgale, they approached a lender called Real People for the loan of R12 000.

A year later she was visited by an agent representing Real People to make repayment arrangements on her sister's student loan as it was in arrears, she said.

Thoane said she agreed to pay a R200 monthly instalment to reduce interest, which she did. But the same year, in 2011, she was served with an attachment order demanding repayment of R26251 from her.

Thoane said she did not understand how the debt skyrocketed to R26251 in a year.

Consumer Line has seen a total bill of R59000 that consists of tracing and collection fees, interest and sheriff of the court fees.

So far, Thoane has repaid R15700 and believes the collecting attorneys are exploiting her.

Curiously enough the attachment order was issued in Alberton though Thoane lives and works in Rustenburg. Sherene Scholtz, a clerk at Tinto Incorporated, said the billing they issued to Thoane in May this year demanding R59000 was issued in error.

"We had a problem with our old system, which means the statement Thoane received previously was incorrect," said Scholtz.

She said Thoane's balance is now R33461. Scholtz said Thoane was charged a tracing fee because the attachment order had to be sent to her by a tracing agent.

Real People had to trace the client, and confirm her employment, so that the tracer could go to her to sign the relevant papers, she said.

Scholtz said Tinto Incorporated were aware of the in duplum rule and insisted that the amount they had billed Thoane did not exceed the capital amount she owed.

In the Supreme Court of Appeal judgment in the case of Margo v Gardner in 2010, the judge said the in duplum rule protects debtors from exploitation by ensuring that their creditors cannot allow interest to accumulate indefinitely.

In this case Gardner owed Margo a certain amount plus interest at 15% per annum from September 1998.

This amount had escalated to R15-million. The dispute in this case was whether the in duplum rule applied and the judge found that it did and ordered that the amount owed be reduced from R15-million to R1.4-million, setting a precedent for other creditors to follow.

In simpler terms, the in duplum rule says that at no given time can the interest on the unpaid arrears exceed the capital amount owed.