An employee is suing her employer alleging she was subjected to years of unwanted sexual attention and threats by a male colleague.

She said his behavior persisted even after she reported it to a supervisor at his unit, and she described how the harassment was allegedly spread through the widespread use of unauthorized communication channels such as WhatsApp.

The action is being taken against ICAP — an arm of the world’s largest interdealer broker — and Citigroup. The complainant alleges that the colleague conducting the harassment was a trader with the power to direct big transactions to her team.

Allegations of failure to supervise, enforce policies

Christine O’Reilly said Benjamin Waters, a trader on the bank’s Delta One desk, called and messaged her repeatedly. She said Waters engaged in years of unwanted advances and harassment toward her, but since he represented a valuable client for her firm, she was compelled to prioritize her company’s financial interests over her well-being, forcing her to tolerate the alleged mistreatment.

Waters was a “high-value Citi trader” with the power to direct billions of dollars in volume to ICAP, according to the complaint. She said Waters’ behavior persisted even after she reported it to a supervisor at his unit.

When he was rebuffed, the trader allegedly threatened to cut off business to her employer. And, according to O’Reilly’s complaint, O’Reilly’s supervisor at ICAP urged her to keep tolerating the advances, unblock him on her social-media accounts, and to apologize to him to keep bringing in the business.

WhatsApp used to bypass corporate oversight

Her complaint says Waters attempted to enter her London hotel room despite her refusal in early 2020, and throughout 2020 and 2021, and that Waters used WhatsApp to bypass corporate oversight and send inappropriate late-night messages asking for O’Reilly’s pictures and trying to meet her in private.

O’Reilly’s negligence claims against Citi allege that the company failed to adequately supervise Waters’ moves and enforce relevant policies to prevent his misconduct. She cited “longstanding failures” in Citi’s internal controls and compliance systems, both of which allowed Waters’ alleged abusive behavior to continue, according to her complaint.

“Despite company policies prohibiting such use, both ICAP and Citi allowed and even encouraged the widespread use of unauthorized communication channels like WhatsApp,” the complaint said.

OReilly lodged an internal complaint at ICAP in March, filed this legal complaint with a federal court in Manhattan earlier this month, and has been on indefinite leave since making the internal complaint.

In recent years, the SEC and CFTC have leveled penalties totaling $200m against Citi for employees’ use of unauthorized messaging platforms such as WhatsApp.