"Businesses and big multinational corporations and tech companies in particular are a key part of our multilateral world of decision-makers, and each one will decide whether to be a force for good or complicit in abuses of power."
Clooney said the digital nature of the world had affected the types of human rights abuses committed, although age-old methods were still being used as well.
"All over the world we still see crimes against humanity committed against minorities, the subjugation of women, the murder of journalists who dare to speak the truth."
But she said autocrats had also innovated to make the most of the digital revolution by adopting new laws to police speech on the web, by harassing dissidents using mass surveillance tools and government-sponsored trolls, and silencing communities through shutdowns of the internet.
She gave the example of one of her clients, Philippines-based journalist Maria Ressa, who was a CNN bureau chief for Asia.
"She reported on misdeeds by her government including a murderous campaign against alleged drug dealers that has killed thousands of Filipino civilians."
Ressa has just been awarded this year's Nobel Peace Prize.
"Yet in the Philippines this talented journalist faces a six-year prison sentence for the crime of cyber-libel and the rest of her life in prison following a host of other spurious charges."
She said the Philippine Government had used online trolls to instigate and amplify disinformation campaigns against her.
"Hate messages on social media directed at Maria at one point reached a rate of 90 messages per hour, all in an attempt to dehumanise her, cast doubt on her credibility and break down her spirit."
Clooney said Maria's case was emblematic of how human rights abuses by governments can involve companies and how online and offline assaults could intersect.
"Oxford University's Internet Institute has reported that social media manipulation by political actors is now prevalent in over 80 countries and that governments are spending millions on private sector cyber troops to drown out other voices on social media."
Clooney said the Facebook campaign by security forces in Myanmar against the Rohingya population had been called the first social media-fuelled genocide.
While in China video cameras with embedded facial recognition technology were used to detect faces belonging to the Uighur population - a group the US had declared to be victims of genocide.
She also pointed to spyware made by the Israeli company NSO that has reportedly been used in state-sponsored attacks on journalists and activists all over the world, including the assassination of Washington Post columnist Jamal Khashoggi by Saudi government agents in Turkey.
But she said just as human rights abuses may be the result of public and private action so it could be with the possible responses to the abuses.
In Ressa's case it was other states that had stepped up. "Many states have condemned the actions of the Philippine authorities, the US Congress has taken steps to impose targeted sanctions ... on Philippine officials complicit in silencing her and other journalists."
Clooney said increasingly it was companies and not just states that were being called upon to take a stand on human rights.
"It is in my view increasingly difficult for businesses to ignore such calls."
She said businesses were increasingly being held to account for human rights abuses in court.
One example was a French concrete company that could be put on trial for giving money to Isis while operating a cement plant in Isis-controlled territory in Syria.
And in another case a tea company was prosecuted in the UK for allowing its female employees to be sexually assaulted by fellow employees while picking tea in Malawi.
"Businesses are more likely to pay attention to human rights if they are to face legal consequences for ignoring them."
But she said they were also being increasingly judged in the court of public opinion.
"Employees, advertisers and clients now routinely expect businesses to be on the right side of human rights issues when it comes to their products, investments and internal governance."
Some businesses were also seeing it as an opportunity because doing good could be profitable too, she said.
One of adidas' best-selling trainers in recent years was made out of recycled ocean plastic.
"Of course sometimes doing the right thing is a calculated decision to pull away."
She said Microsoft and IBM had opted not to sell facial recognition technology until there was regulation in place.
A short-term loss of profit may avoid long-term harm to the brand.
"As one US executive put it: This is not just about being goody-goody it's good business."
Clooney said she believed progress could be made on human rights if liberal democracies use the tools they have to pressure illiberal autocracies and if companies do what they can to move the needle in the right direction.
"You can always shame bad actors. Some governments that trample on human rights don't care about bad press, and good governments are not always willing to impose consequences when abuses are committed by others."
But sometimes the only option was to get the private sector involved especially as so many global challenges called for a multi-stakeholder response.
She pointed to New Zealand's Christchurch Call - an initiative to police terrorist content on the web after the Christchurch terror attack.
"It partnered not only with 55 other states but with 10 leading tech companies to do this."
She said businesses were not only incidental but often absolutely essential to advance human rights in the interconnected world.
"We have to wage justice and I believe we all have a part to play."
