The bank and the accused banker deny any wrongdoing. The proceedings, which began on Monday of last week, continued through this week and are scheduled to run until early March.
The indictment centres on relationships that Credit Suisse and its ex-employee had with former Bulgarian wrestler Evelin Banev and multiple associates, two of whom are also charged in the case.
The female banker, who is accused of helping conceal the criminal origins of the money through more than 146 million Swiss francs in transactions, appeared in the Federal Criminal Court in Bellinzona in southern Switzerland along with her managers who gave evidence. The events unfolded between 2004 and 2008.
A Credit Suisse spokesperson said the bank has rejected all allegations and that it was convinced its former employee was innocent. Credit Suisse disputes the illegal origin of the money, a source familiar with its thinking commented, saying that Banev and his circle operated legitimate businesses in construction, leasing and hotels.
Banev is not facing charges in Switzerland but was convicted in Italy of drug trafficking in 2017 and in Bulgaria in 2018 for money laundering. He was arrested in September in Ukraine as countries including Bulgaria and Romania sought his arrest.
In Sofia, his attorney said last week that Banev denied any involvement in laundering money from drug trafficking through Credit Suisse. The former Credit Suisse banker whose identity cannot be reported under Swiss privacy rules said she told her managers of events, including two murders, but that they decided to pursue the business nonetheless.
Banker raised murder cases with her manager
In an email from June 2005 read out in court last week, a Credit Suisse banker played down press reports linking the murder of one of Banev's associates a month earlier with drug trafficking.
"After the homicide, we have decided to continue the business relationships," the banker wrote in the email. "The said (short and imprecise) article linking the murder to Spanish cocaine...has not been confirmed."
Roughly two years later, the victim's mother was also murdered shortly before she was due to give a statement as part of an investigation into Banev, the female banker later told the court, prompting her to raise the matter with her managers.
Banev, whose lawyer declined to comment further on Thursday, was in custody at the time, charged with participating in an organised crime group that aimed to launder money. "The reaction I received when talking with my hierarchy, the questions were: was the person killed a bank client? No, she was not," the banker told the court.
"Is she in any way linked to the bank, do you know her?" she said, recalling the conversation. "I said: 'No, never met her'. And then the reaction was, well then what is your problem?"
Matter entrusted to the internal legal team
The court heard that the banker received bonuses of 122,000 Swiss francs in 2006 and 180,000 francs in both 2007 and 2008.
Taking the stand to give evidence, the banker's managers said this week they could recall little of events at the time and said they had trusted the matter to the bank's legal and compliance department in line with internal rules regarding funds under investigation.
"The whole process is with legal and compliance," one of the banker's former managers told the court. "The relationship manager is asked not to inform colleagues when legal and compliance considers it important to inform different hierarchy, then they do it."