President Donald Trump and his lawyers still believe he can block people on Twitter because he doesn’t like their views, so today we’ve filed a brief telling a court, again, that doing so violates the First Amendment. We’re hopeful that the court, like the last one that considered the case, will side with the plaintiffs, seven individuals blocked by Trump who are represented by the Knight First Amendment Institute. As we explain in the brief, the case has broad implications for the public as social media use by the government becomes more and more ubiquitous.

Trump lost the first round of the case when a judge sided with the plaintiffs, who include a university professor, a surgeon, a comedy writer, a community organizer, an author, a legal analyst, and a police officer. The judge agreed with the Knight Institute, which argued that the interactive spaces associated with the @realDonaldTrump account are “public forums” under the First Amendment, meaning that the government cannot exclude people from them simply because it disagrees with their views. In a brief filed in round one, we argued governmental use of social media platforms to communicate to and with the public—and allow the public to communication with each other—is now the rule of democratic engagement, not the exception. As a result, First Amendment rights of both access to those accounts and the ability to speak in them must apply in full force.

The ruling in round one was a great victory for free speech and recognizes that in the digital age, when a local, state, or federal agent officially communicates, through Twitter, with the public about the government’s business, he or she doesn’t get to block people from receiving those messages because they’ve used the forum to express their disagreement with the official’s policies. Trump was forced to unblock the plaintiffs.

The president’s attorneys are now trying to convince an appeals court to overturn this ruling, making the same arguments they made in the lower court that @realDonaldTrump, Trump’s Twitter handle, is the president’s private property and he can block people if he wants.

In the brief we filed today we’ve told the appeals court that those arguments—which were wrong on the law in the first place—are still wrong. The president has chosen to use his longtime Twitter handle to communicate his administration’s goals, announce policy decisions, and talk about government activity. Similarly, public agencies and officials, from city mayors and county sheriff offices to U.S. Secretaries of State and members of Congress, routinely use social media to communicate official positions, services, and important public safety and policy messages. Twitter has become a vital communications tool for government, allowing local and federal officials to transmit information when natural disasters such as hurricanes and wildfires strike, hold online town halls, and answer citizens’ questions about programs.

When governmental officials and agencies choose a particular technique or technology to communicate with the public about governmental affairs, they have endowed the public with First Amendment rights to receive those messages. And this right, we told the appeals court, is infringed when government denies access to these messages because it disagrees with someone’s viewpoints.