Slaughter and May has advised client Hitachi on its settlement with the African Development Bank, ending a three-year probe into allegations of bribery at the Japanese company.

The bank launched an investigation into claims Hitachi’s German and South African subsidiaries engaged in “sanctionable practices” to win a £3.3bn contract to build the Medupi power station in 2009.

Bretton Woods Law Chambers was instructed by the bank’s corruption department to advise on the deal, which was signed on Wednesday (2 December).

The agreement includes an undisclosed financial payout by Hitachi and a one-year ban on bidding on projects funded by the bank in South Africa.

The deal follows Hitachi settling with US regulator the Securities and Exchange Commission (SEC) in September for $19m over similar allegations. The penalty fine closed the SEC’s parallel investigation into concerns Hitachi made the improper payments in the power plant bid.

The African Development Bank said the one-year debarment would end once Hitachi “enhances its integrity compliance programme” standards set by the bank’s compliance guidelines. 

Hitachi issued a statement following the deal saying it is “committed to ethical business conduct” and compliance is a top priority for the group.

The Bretton Woods Law team was managed by barristers Lee Marler, Neil Macaulay and Alex Haines.

Slaughters’ mandate on the corruption deal follows a run of similar client work for the UK firm. It was recently drafted in by Rolls-Royce to advise on an investigation led by the Serious Fraud Office (SFO) into claims it bribed officials in Indonesia.

The late instruction is understood to follow talks between the aerospace company and the SFO over the possibility of reaching a deferred prosecution agreement (DPA). The SFO opened the formal criminal investigation in December 2013.