The former senior partner of law firm Binks Stern was guilty of fraudulent misrepresentation when he wrote a letter for disgraced tycoon Roger Levitt that helped him receive a £2.5m loan.

The court of appeal last week overturned a High Court ruling, which had originally cleared William Binks. It ordered his firm – now part of Morgan Bruce – to pay £3.8m to merchant bank Henry Ansbachers.

Binks wrote to Ansbachers in 1990 at Levitt's request confirming that he was acting for Levitt in the sale of some of his shares, but not revealing that the sale had already gone through. Binks maintains that he did not know why Levitt had requested the letter. As a result of Binks' letter, Ansbachers loaned Levitt £2.5m thinking Levitt would be able to pay the money back from the share sale.

When the next day, Levitt told Binks that he was trying to get a loan from Ansbachers, the lawyer refused to act for Levitt on the loan transaction and returned the documents to

Ansbacher's lawyers Clifford Chance. However, he did not retract his letter to Ansbachers nor tell his partners at Binks Stern. Instead, he wrote a statement about his actions of the previous two days and got his secretary to witness it.

The three Lord Justices, led by Lord Justice Nourse, said of the High Court judge, Mr Justice Knox: “We believe that out of a natural sympathy for the predicament in which Mr Binks found himself, he failed to appreciate the inevitable consequence of his findings”, that Binks knew that he was no longer acting for Levitt on the share sale when he wrote the letter to Ansbachers. “If he was innocent in the matter, why did he not inform his partners of it?” they asked.

Binks retired from Binks Stern in 1992, aged 70, and the firm merged with Morgan Bruce two years later.