The lead international lawyer for Jimmy Lai, Caoilfhionn Gallagher, has said she "won't be intimidated" from his case.
The media mogul and democracy activist is on trial in Hong Kong on various charges.
The 77-year-old has pleaded not guilty to two charges of conspiracy to collude with foreign forces, and a charge of conspiracy to publish seditious material.
Closing arguments are being held this week and are expected to last several days but it could take weeks, or even months, before judges arrive at a verdict.
Ms Gallagher told RTÉ's Behind the Story podcast she has faced several threats just for doing her job.
"It’s taken a range of different forms – some of it just is being in the slipstream of being Jimmy Lai’s lawyer," she said.
"Some of it is abuse directed at Jimmy Lai, which then comes my way simply because I represent him, but some it is much more chilling than that.
"It’s involved very extensive hacking attempts, impersonation attempts, physical surveillance".
'Have to be quite careful’
Ms Gallagher said there are places she cannot travel to on account of her work.
"There are now many places I can’t travel to – for example, any country at all that has an extradition arrangement with China or Hong Kong is off our list for personal or professional travel.
"I just have to be quite careful when travelling to ensure that I’m not putting myself more at risk.
"The bottom line is if they’re coming after me as the lawyer, they’re only doing it because of how much they hate my client.
"In order to continue doing a job for Jimmy Lai and my other clients I need to make sure that I’m safe and continue to be free".
‘Multiple rape threats’
Ms Gallagher told Katie and Paul while this is not the first time she has faced intimidation, it feels different.
"I’ve had much abuse for my work, even just acting on things like reproductive rights and abortion rights for individuals from Northern Ireland, for example," she said.
"What’s been happening on Jimmy Lai’s case is very different because it doesn’t feel as if I’m being targeted simply in a secondary way… this is a situation where really I’m being targeted in a primary way".
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Ms Gallagher said on a key day while presenting to the United Nations about Mr Lai’s case she woke up at 5am in a Geneva hotel room "to multiple different rape threats and death threats – many of which named my children – and gave some personal detail which meant they knew where I lived, they knew where I was".
"Later that day I and a female colleague were followed around – both in the United Nations building and outside also – including by a car with diplomatic plates.
"On that same day I also had multiple messages from my bank to say that there had been hacking attempts from something like 27 different countries".
‘Won’t be intimidated’
Ms Gallagher said she becomes more determined when such threats are made.
"It’s all designed to intimidate you and to stop you doing your job," she said.
"Just speaking frankly: I won’t be intimidated and when those kind of actions are taken, they just make me more determined then ever to do a job for my client.
"What kind of lawyer would I be if I was frightened off by that kind of behaviour?" she added.
You can listen to Behind the Story which is available on the RTÉ Radio Player.
You can also find episodes on Apple here, or on Spotify here.
