The Israeli reservist left Brazil in a hurry this week after a Brazilian judge ordered an investigation into whether he committed war crimes in Gaza.

Israeli consular officials helped soldier Yuval Vagdani fly out of the country on Sunday after the order became public. It was prompted by a criminal complaint filed by a Belgium-based non-profit group, the Hind Rajab Foundation, which “focuses on abusive legal actions against perpetrators, accomplices and instigators of war crimes and crimes against humanity in Palestine”.

On Wednesday, the Israeli military announced that it would no longer identify soldiers by name in the media, “for fear of arresting soldiers abroad.”

Mr. Vagdani was deployed to Gaza following the October 7, 2023, attack by Hamas, which triggered Israel’s invasion of the territory in a campaign aimed at defeating and destroying Hamas.

According to the complaint of the Hind Rajab Foundation, Mr. Vagdani posted videos and photos from Gaza on social media showing him destroying civilian homes and other buildings. Group claims those actions were a systematic attempt to impose unbearable living conditions on the civilian population, in violation of international law. (The Times has not independently verified that evidence.)

A Brazilian judge decided the allegations should be investigated and referred the matter to federal police. In recent months, several similar criminal charges have been filed against Israeli soldiers on vacation, including in Cyprus, Sri Lanka, Argentina and Chile.

Mr. Vagdani, whom the Times could not reach for comment, arrived in Israel on Wednesday.

In an interview with Khan, Israel’s public broadcaster, he admitted to posting a video of the building being blown up. “That’s what they saw and they wanted to investigate me,” he said. “They turned it from one house into 500 pages, they thought I killed thousands of children and who knows what.”

Mr. Vagdani also told Kan that he was on New music festival near the Gaza border on October 7, 2023 and escaped a massacre there.

Israeli officials downplayed the seriousness of the cases, noting that none of the criminal charges led to arrests. “We understand that part of this phenomenon is driven by pro-Palestinian activists and is based on open-source intelligence,” said Lt. Col. Nadav Shoshani, an Israeli military spokesman.

The open-source methods in question are social media posts, which pro-Palestinian groups now use as evidence to seek criminal charges against soldiers when they travel abroad.

Universal jurisdiction

The combination of social media and international tourism – alongside a very old body of law – could open up a new arena in international criminal law.

Universal jurisdiction, one of the oldest principles of international law, considers that certain crimes are so serious that any country in the world can initiate criminal proceedings against the perpetrators. In the 18th century, this rule was used for crimes such as piracy; more recently, it has been used to prosecute genocide and war crimes.

Israel relied on universal jurisdiction to prosecute Adolf Eichmann, a high-ranking Nazi official, for crimes against humanity committed during the Holocaust. Spain relied on it when it sought the extradition of Augusto Pinochet, the former Chilean dictator, to face charges of torture and other crimes. And in more recent examples, several European countries have relied on the principle of trying Syrian officials for war crimes and crimes against humanity. Belgium prosecuted Rwandans accused of involvement in the 1994 genocide before its courts.

For decades, these cases were relatively rare and mostly targeted high-ranking officials. “There has been this tendency to focus on higher levels to maximize impact, and also because at higher levels behavior is sometimes actually better documented than lower levels,” said Yuval Shany, a professor of international law at the Hebrew University of Jerusalem.

A local prosecutor had a difficult time obtaining evidence of a war crime allegedly committed in another country. That changed with social media. “Technology is coming to bridge the gap, because once you’ve filmed, documented yourself starting a war crime, it’s much easier to prosecute you, even in a court half a world away,” Mr Shany said.

Experts say Israeli soldiers have uploaded their videos and other images in Gaza saying and doing things that could be interpreted as evidence of serious crimes, including the destruction of civilian homes and property, and calling for the expulsion or extermination of Palestinians.

While the clips on social media can be taken out of context or misinterpreted – and Israel has accused Hamas of using civilian infrastructure for military purposes – “some of them look very bad”, Mr Shany said. “There’s this potential level of accountability that we haven’t seen in wars before, simply because it’s been too hard to create evidence.”

However, while social media evidence is compelling, it is unlikely that it alone will be enough to ensure a successful prosecution, said Rebecca Hamilton, a law professor at American University and a former attorney in the Office of the Prosecutor of the International Criminal Court: “Social media posting does not constitute a case of a war crime.”

A new legal strategy

The Hind Rajab Foundation claims to have collected evidence against about a thousand Israeli soldiers. He also follows their foreign trips on social media as they post about their vacations and then promptly file criminal charges against the countries they visit.

Dyab Abou Jahjah, president of the Hind Rajab Foundation, said soldiers who respect international law have nothing to fear from his organization. “We are not organizing a witch hunt against Israeli soldiers,” he said. “We are bringing cases against soldiers for whom we have evidence that they are individually responsible for war crimes.”

Unlike senior leaders, lower-level soldiers typically lack diplomatic immunity or the resources to investigate jurisdictions that could make them vulnerable to war crimes complaints.

Of course, an NGO filing a criminal complaint is not the same as a prosecutor actually filing an indictment, much less an arrest or conviction.

The Israeli government has taken actions that suggest it is concerned about the criminal charges. The government, which insists its forces in Gaza acted in accordance with international law, has formed an interagency team to assess the legal risk to soldiers and reservists abroad. And the foreign ministry recently issued a public warning to Israelis that their social media posts could be used to initiate legal proceedings against them in other countries.

These cases may not have to end up in a courtroom or even result in arrests to have an impact. The public may find it difficult to tolerate the possibility that soldiers may not be able to travel abroad without risking imprisonment.

Traveling abroad is extremely important to Israelis, Mr. Shany said. “So I think there’s an idea that this is actually an unacceptable risk and that the government military has to make it go away.”

Isabel Kershner and Aaron Boxerman contributed reporting from Israel, Ephrat Livni contributed reporting from Washington, DC, and Jack Nicas contributed reporting from Brazil.

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