LONDON — A former trader at UBS accused of causing a multibillion-dollar loss was ‘‘playing God’’ with the Swiss bank’s money, prosecutors told a jury here Thursday.
During closing arguments in the eight-week court case, Sasha Wass, the lead prosecutor, said that Kweku M. Adoboli, a former UBS trader in London, had ‘‘arrogantly’’ sidestepped the firm’s rules and carried out risky trading activity from 2008 to 2011.
‘‘There were no accidental losses. They were the result of planned, purposeful, unhedged trades,’’ Wass told the jury. ‘‘Mr. Adoboli is a gambler, not a legitimate investment banker.’’
Adoboli, 32, is charged with six counts of fraud and false accounting in connection with a $2.3 billion loss at the Swiss bank. If convicted, he could face more than 10 years in prison. He has pleaded not guilty to the charges.
The defense is expected to give its closing argument Friday, and the jury will begin deliberations early next week.
Adoboli was arrested in September 2011 after several people in the bank’s risk compliance unit raised concerns about his trading activity. Just hours before, Adoboli, an investment banker born in Ghana, had walked out of UBS after writing an e-mail to colleagues that said he had exposed the firm to potential multibillion-dollar losses, prosecutors said.
Over four years, Adoboli created fictitious trades to hide his trading losses and concealed his activities from colleagues, the prosecution said.
In his defense, Adoboli has tried to show that the bank knew about his activities and encouraged him to continue the reckless behavior.
‘‘Like any gambler, Mr. Adoboli thought he had a winning hand,’’ Wass told the jury. ‘‘He was playing God with the bank’s money.’’