On Friday, a New York City judge ruled that President Donald Trump must testify in a case involving an incident during a protest outside Trump Tower in 2015.

Bronx-based Judge Doris Gonzalez ordered that Trump submit a video testimony before the trial which is set to start Thursday, ruling that his testimony is “indispensable.”

The incident involves a protest outside Trump Tower where security guards became violent with protestors. The protestors claim that Trump, his campaign and business should be held liable for the actions of the security guards. They argue that even if he did not give the guards direct commands to engage with protestors in the way they did, they are employed by his company and therefore Trump should take full responsibility for the incident. In addition, they argue that Trump’s campaign trail rhetoric gave the impression that violence would be condoned.

According to the initial court filing, the case centers around a September 2015 campaign protest in front of Trump Tower in New York City, where two protesters wore parody Ku Klux Klan outfits to protest Trump’s rhetoric on illegal immigration. The lawsuit is being brought forth by five men. The men allege that Trump head of security, Keith Schiller, hit a protester, Efrain Galicia, in the head after Galicia tried to stop Schiller from taking their large cardboard signs, that read “Make America Racist Again.” The filling reads that when Galicia tried to hold onto one of the signs, Schiller ripped it away from him, tearing it to pieces. Galicia then tried to prevent Schiller from destroying another sign and was met with a blow to the head.

Schiller responded claiming that he was just trying to make space on the sidewalk and that he struck the protester only after the man grabbed him suddenly from behind. In his sworn testimony, Schiller says the protestors and their banners were a threat to public safety, because if there were an emergency, there would be no way for an ambulance to gain access to the building. Schiller claims, that Galicia grabbed him from behind in order to reach for his gun. When realizing the situation, Schiller said he was prompted to swing around and hit the protestor with his open palm. Schiller states that this act, used the “minimal amount of force to get him off of my firearm and off of my body.”

The plaintiffs are seeking an injunction to forbid the Trump security officials from interfering with public protests and are seeking damages.