How we helped a US-based victim stop cross-border online harassment from an ex’s UK partner using legal action and privacy law
Sadly, harassment by an ex or their new partner is far more common than many people realise. Whether the harasser is male or female, this kind of behaviour can affect anyone and often escalates quickly from unpleasant messages to sustained online and even physical abuse.
When an ex or their new partner crosses the line into harassment
If you've started receiving harassing messages from your ex’s new partner, you’re not alone, and sadly, this sort of situation happens far more often than people might think. Whether it's a new girlfriend threatening the ex-boyfriend’s former partner, or a former boyfriend targeting his ex and her current partner, the harassment can come from any gender and take many forms.
It usually starts small, perhaps with a few angry texts or social media comments, but can quickly escalate into relentless and damaging behaviour. In this case study, we look at how our legal team helped a client in New York put an end to a sustained campaign of digital harassment from a woman in the UK, using UK internet law.
The case involved cross-border elements, racial abuse, threats to reputation, and invasion of privacy. We resolved it without court action, and most importantly, the harassment stopped for good.
How a romantic relationship turned into a campaign of harassment
Our client, a professional working in New York, had started dating a man who frequently travelled between the UK and the US. Unknown to her, he was also in a long-term relationship with another woman in the UK.
When the UK-based girlfriend found out about our client, she began calling, messaging, and threatening her. The abuse started with a WhatsApp video call, where the girlfriend threatened her and accused her of ruining her relationship. From there, it escalated to a stream of messages, some of which included racial slurs, personal attacks, and threats to destroy her career.
In some messages, the harasser claimed she had accessed the man’s private phone and group chats and sent the client images of other women, presumably to shame or intimidate her. Our client rightly avoided responding, but the abuse didn’t stop.
The psychological and reputational toll of online harassment
Although the harasser was in another country, the effects on our client were immediate and profound. She felt her privacy had been completely violated. She feared the threats to her reputation would become real, especially given the harasser’s knowledge of her personal details and the aggressive nature of the messages.
She also feared for her safety, particularly because the harasser had shown signs of being able to monitor her communications and social activity. This situation is not unusual. Many people find themselves victims of harassment from someone they’ve never met in person.
Online harassment, especially when it involves threats to your career or racial abuse, can have devastating emotional effects and can escalate without warning.
Why this is harassment under UK law, even if you're based outside of the UK
Under UK law, harassment is both a civil and a criminal offence. It does not matter whether the harassing messages are true or false, or whether they are published online or sent privately. What matters is the persistent and unwanted nature of the contact, and whether it causes alarm, distress, or fear.
The law also considers repeated threats or invasions of privacy (like accessing personal messages or threatening to post private information online) as forms of harassment. Importantly, in cross-border cases like this one, if the person doing the harassing is based in the UK, UK harassment law may still apply, even if the victim is overseas.
Cease and desist letters as a first step to stop harassment
After reviewing the case, we advised our client to send a cease and desist letter. This is often a highly effective tool in online harassment cases. The letter lays out the harasser’s illegal conduct, demands that they stop immediately, and warns of legal consequences if they continue- including a potential court injunction, financial penalties, and a criminal investigation.
We prepared a comprehensive letter that clearly detailed the harasser’s behaviour, the legal implications, and what would happen next if she didn’t comply. We also included the offer of a legally binding undertaking. An undertaking is a legally binding contract that carries many of the same obligations as a court-imposed injunction, but it is entered into voluntarily rather than being ordered by a judge. It serves as a strong legal deterrent while avoiding the need for a lengthy court case.
Offering an undertaking is part of our broader approach to achieving the result our client needs in the most cost-effective way, helping them move on swiftly. The appropriateness of an undertaking depends on each individual client and their unique priorities, and in many cases, it provides just the right level of assurance to allow them to put the harassment ordeal behind them.
Avoiding court proceedings can save significant legal costs and, more importantly, spare clients the prolonged stress of litigation. For many people facing harassment, putting the ordeal behind them quickly is what matters most. Each client has different goals and sensitivities, and what resolution is sufficient depends on what will give them peace of mind. In this case, the undertaking was the right solution.
Serving harassment notices internationally
At first, serving the cease and desist letter proved challenging. Twice we made attempts to serve the harassment cease and desist letter in person unsuccessfully. Finally, on the third attempt, service was successful.
Shortly after, the harasser responded by signing a formal undertaking not to contact our client again. This marked a significant step forward, as it showed a willingness to resolve the matter without court intervention. Unfortunately, several months later, the harasser appeared to have resumed her behaviour and sent another round of abusive messages.
We acted swiftly, issuing a second and more forceful legal letter which clearly warned of imminent legal proceedings if the behaviour did not stop. This time, the warning had the desired effect and the harassment ceased completely.
This escalation reinforced the legal consequences and reminded the harasser that compliance with the undertaking was not optional. The client was ultimately able to regain peace and move forward with confidence that legal support would remain in place should anything recur.
Why we didn’t go straight to court
Taking someone to court for harassment is an option, but it can be expensive and emotionally exhausting. In this case, we opted for a more strategic, layered approach: start with a cease and desist letter, offer the opportunity for the harasser to avoid court by signing an undertaking, and keep legal escalation as a credible consequence. This avoids unnecessary cost for the victim and is often enough to resolve the situation.
The lawyers’ thoughts on the case
This case is a clear example of how online harassment can evolve out of romantic conflict and how seriously it can affect someone’s personal and professional life. What stood out here was not only the persistent nature of the messages and the racial abuse, but also the cross-border challenge it presented.
Our client was based in New York, while the harasser lived in England, creating a legal situation where two jurisdictions were involved. This often poses complications around service, enforcement, and which country's laws apply. However, English law has clear principles for determining jurisdiction in harassment cases.
Since harassment is treated as occurring where the victim feels distress, jurisdiction is typically established based on the victim’s location. In this case, we were able to proceed under UK law because the harasser was based in England. Our client had the strength not to retaliate or engage, which helped keep the legal case clear and focused.
Beyond the jurisdiction issues, this was almost a textbook example of how cease and desist letters, backed by strong legal knowledge and a credible threat of further action, can bring online harassment to an end without dragging clients through a long court process, even in cross-border cases.