Ukrainian emergency employees work at a maternity hospital damaged by shelling in Mariupol, Ukraine, on Wednesday, March 9, 2022.

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CNN  — 

A year into Russia’s brutal and unprovoked invasion of Ukraine, the US has seen enough.

“In the case of Russia’s actions in Ukraine, we have examined the evidence, we know the legal standards, and there is no doubt: These are crimes against humanity,” Vice President Kamala Harris said at the Munich Security Conference this weekend.

“To all those who have perpetrated these crimes, and to their superiors who are complicit in those crimes, you will be held to account.”

The declaration marks the strongest accusation yet from the US as it seeks to punish Moscow for its war of aggression.

The US government declared last March that members of the Russian armed forces had committed war crimes in Ukraine. President Joe Biden has gone as far as saying that atrocities at the hands of Moscow’s troops qualify as “genocide.”

While the “crimes against humanity” determination is significant, it remains largely symbolic for now. It does not immediately trigger any specific consequences, nor does it give the US the ability to prosecute Russians involved with perpetrating crimes.

However, it could provide international bodies, such as the International Criminal Court, with evidence to effectively try to prosecute those crimes.

Here’s what you need to know about how these kinds of crimes are prosecuted on the international stage.

What are crimes against humanity?

A crime against humanity is defined by the International Criminal Court as an act “committed as part of a widespread or systematic attack directed against any civilian population, with knowledge of the attack.”

This can include, among other things, murder, extermination, torture, enslavement, sexual violence, deportation or forcible transfer of population or other inhumane acts.

“We reserve crimes against humanity determinations for the most egregious crimes,” Secretary of State Antony Blinken said in a statement Saturday. “These acts are not random or spontaneous; they are part of the Kremlin’s widespread and systematic attack against Ukraine’s civilian population.”

What evidence did the US cite?

Harris in her speech outlined specific instances that have peppered news clips and official reports.

“First, from the starting days of this unprovoked war, we have witnessed Russian forces engage in horrendous atrocities and war crimes,” Harris said.

“Russian forces have pursued a widespread and systemic attack against a civilian population – gruesome acts of murder, torture, rape, and deportation. Execution-style killings, beating and electrocution,” she added.

“Russian authorities have forcibly deported hundreds of thousands of people from Ukraine to Russia, including children. They have cruelly separated children from their families.”

Harris’ speech cited evidence of indiscriminate Russian attacks that deliberately targeted civilians, including the bombing of a maternity hospital that killed a pregnant mother and of a theater in Mariupol, where hundreds were killed.

The vice president spoke of the horrific images out of Bucha that showed men and women shot and left to rot in the streets and reports by the United Nations of a 4-year-old girl who was sexually assaulted by a Russian soldier.

As it was when the US government declared that Russia committed war crimes last March, it remains to be seen whether there will be any accountability and whether Russian President Vladimir Putin himself will be forced to bear any responsibility.

“We will continue to support the judicial process in Ukraine and international investigations because justice must be served. Let us all agree, on behalf of all the victims, known and unknown: Justice must be served,” Harris said.

What is the International Criminal Court?

Located in The Hague, Netherlands, and created by a treaty called the Rome Statute first brought before the United Nations, the International Criminal Court operates independently.

Who falls under the court’s jurisdiction?

Most countries on Earth – 123 of them – are parties to the treaty, but there are very large and notable exceptions. That’s key for this story, as neither Russia nor Ukraine — nor for that matter, the US — are part of the agreement.

Then how can the ICC address these allegations?

The court tries people, not countries, and focuses on those who hold the most responsibility: leaders and officials. While Ukraine is not a member of the court, it has previously accepted its jurisdiction. Accused Russian officials could theoretically be indicted by the court. However, the ICC does not conduct trials in absentia, so they would either have to be handed over by Russia or arrested outside of Russia. This seems unlikely.

So could it affect the conflict?

An ICC investigation could affect any diplomatic space for negotiations, with Putin and other accused perpetrators not wanting to risk arrest if they travel outside the country. It could also weaken Putin’s popularity at home, with Russians losing faith in his ability to lead.

How long do these investigations take?

If justice in general moves slowly, international justice barely moves at all. Investigations at the ICC take many years. Only a handful of convictions have ever been won.

A preliminary investigation into the hostilities in eastern Ukraine lasted more than six years – from April 2014 until December 2020. At the time, the prosecutor said there was evidence of war crimes and crimes against humanity. Next steps were slowed by the Covid-19 pandemic and a lack of resources at the court, which is conducting multiple investigations.

What is Russia’s response?

Anatoly Antonov, Russia’s ambassador to the United States, cast the crimes against humanity accusation as an attempt to “demonize” Russia, according to state news agency TASS.

“We consider such insinuations as an attempt, unprecedented in terms of its cynicism, to demonize Russia,” Antonov said this weekend.