During the dedication ceremony for the new American embassy in Jerusalem on Monday, about 200 left-wing and Israeli Arab demonstrators on a nearby street protested the transfer of the embassy. Other than a neighborhood resident who tried to spray them with water from her balcony, the demonstration, which was led by Arab Knesset members and members of the Higher Arab Monitoring Committee, was proceeding uneventfully. There were no confrontations with nearby right-wing counterdemonstrators or with the police who surrounded them and separated them from their ideological opponents.

The peaceful scene didn’t last long, however. At one point, the left-wing protesters pulled out Palestinian flags and began waving them. It took only a few minutes until police stormed into the crowd of demonstrators and forcefully ripped away the flags. “They came charging like a bull seeing a red flag,” one demonstrator recounted.

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In the process, what had begun as a quiet protest turned into a violent clash that ended only after the police pushed and shoved the protesters and ultimately dispersed them. “The police went crazy,” said Joint List Knesset member Aida Touma-Sliman, who added that none of the demonstrators had even touched a police officer. “They set upon us when they saw a sign with a Palestinian flag, “ she recounted, “as if they had seen – I don’t know what – and started hitting. I got my share and others got theirs.”

After the demonstrators were dispersed, the police saw to it to also remove the large sign that the Peace Now organization had placed – after securing a permit – opposite the new embassy. The sign featured a Palestinian flag alongside the Israeli flag.

With regard to this week’s demonstration near the American embassy in Jerusalem, the Israel Police said in response: “Contrary to what has been claimed, the Israel Police actually permitted the expression of protest and also coordinated the conditions in advance with the demonstrators who chose to blatantly violate them. Nevertheless, the police were prepared at first to enable the existence of the protest. At a certain stage, beyond the flying of the flags, there were calls of incitement, manifestations of violence toward the police, and deliberate provocation aimed at disturbing public order in violation of the law and the agreed-upon conditions for the demonstration.”

Fourteen arrests were made, the police said, for disturbing the peace, clashing with police or not obeying their orders. The right to protest is a fundamental one, the police acknowledged, but added that it is not absolute, and the police have an obligation to prevent public disturbances.

The police, the statement continued, direct their enforcement at those disturbing public order and breaking the law and not at those waving flags. “The Israel Police will continue to permit freedom of expression and protest and at the same time act against incitement, violence and disturbances of public order,” the statement said in part.

The embassy protest followed a number of others in recent months, however, in which the police confiscated Palestinian flags from demonstrators even at quiet protests. It’s a new practice, protesters tell Haaretz, saying that until a few months ago, there were no problems in flying the Palestinian flag at demonstrations.

The reason for the change is not clear and it is not the result of any new law banning public display of the Palestinian flag. The flag has even been displayed at the Prime Minister’s Residence in the presence of Palestinian President Mahmoud Abbas. The new policy seems to have been put in practice around mid-December, sources say, following U.S. President Donald Trump’s announcement on December 6 about the relocation of the American embassy to Jerusalem.

The policy has not been confined to Jerusalem. One of those present at a left-wing demonstration at Ben-Gurion University of the Negev in Be’er Sheva this week said that after a confrontation with right-wing counter-protesters, the police demanded that Palestinian flags be put away. “They said flying them was not allowed,” the source said.

Demonstrators who spoke with Haaretz said police officers in the field aren’t necessarily claiming that the display of the flag is illegal but they imply that it could prompt a reaction. This could include a disturbance of the peace or incitement but the explanations appear to vary, and the police response is not uniform.

Although the display of the flags in Jerusalem and Be’er Sheva have sparked a police response, their appearance at other demonstrations, in the northern Israeli Arab town of Umm al-Fahm and elsewhere in the north, did not prompt any police intervention. The same was true last month on Israeli Independence Day when, thousands of Israeli Arabs demonstrated near the Atlit exit of the coastal highway south of Haifa and displayed the Palestinian flag with the approval of the police. Ironically, in that case, a right-wing counterdemonstrator was arrested on suspicion of disturbing the peace after unfurling an Israeli flag and refusing to halt his protest.

The incident prompted a Knesset Interior and Environment Committee hearing two weeks ago where an Israel Police official made it clear that there is no legal prohibition against flying the Palestinian flag. “We always say that sometimes there are events in in our Middle East in which we too as police need to take an anti-nausea pill and get on with the day,” said Police Commander Shimon Ben-Shabo.

It appears, however, that Ben-Shabo’s comments aren’t always reflected in the field. As far back as last June, a left-wing activist was detained while on his way to a demonstration. After the fact, it became apparent that a woman had called the police to complain that he was flying a Palestinian flag near the Be’er Sheva central bus station. The Association for Civil Rights in Israel inquired with the police about the incident and was told that indeed flying the flag is not a criminal act and that the relevant parties had been instructed to inform police officers in the field of this.

But ACRI says the official directives of the police are otherwise. “In accordance with the provisions of the law and directives of the attorney general,” ACRI stated, “in any case in which a suspicion is raised of a high probability that flying the flags will lead to disturbance of public peace or in any case that raises the suspicion of a violation of Section 4 of the Prevention of Terrorism order, the police officer is authorized to remove these flags and to carry out enforcement activity accordingly.”

The legality of displaying the Palestinian flag — originally the flag of the Palestine Liberation Organization — came before the High Court of Justice in the 1990s following Israel’s recognition of the PLO as part of the Oslo peace process. The court ruled that it was not illegal.

Nevertheless, according to data provided by the Movement for Freedom of Information, between 2011 and 2016, a total of 96 police investigations were opened against citizens for flying the Palestinian flag. The police said only 10 of them involved just flying the flag, while the others involved other actions as well.

With reporting by Almog Ben Zikri.