When powerful government agencies don’t like what you have to say, they have many tools to shut you down. One of the most effective is putting you under a microscope.

In the early years of the Obama administration, newly formed conservative groups seeking tax-exempt status were subjected to lengthy delays and inappropriate demands for information, preventing the Tea Party from operating at full strength.

Then there was the John Doe fiasco in Wisconsin, which saw conservative activists subjected to pre-dawn police raids as part of a sprawling investigation ultimately shut down by the state supreme court. Even when a group is not charged with violating the law, constantly being watched and hassled by the government takes a heavy toll.

More recently, conservatives and libertarians have criticized states like California for demanding nonprofits turn over supporters’ names and addresses as a precondition for fundraising in the state. A lawsuit against California revealed that the state had carelessly put the private information of Americans who donated to any registered charity online, without password protection. That means not just rogue bureaucrats but private parties, or even foreign entities, could surveil and harass Americans who support certain causes.

If there is a silver lining, it is that as the government continues to overreach, more people become aware of the dangers of surveilling political advocacy. Now many left-leaning groups are also speaking out against government harassment, in response to U.S. Customs and Border Protection’s (CBP) clumsy efforts to track and monitor activists, attorneys, and journalists at the U.S.-Mexico border.

Secret Databases Should Concern Everyone

CBP, the FBI, and other federal agencies reportedly constructed a secret database of journalists, activists, and attorneys working on immigration issues at the border. The agencies used the database to track and detain individuals who advocated for migrants’ rights, not those who committed crimes. Some of those included in the database even had alerts placed on their passports.

If law enforcement has a legitimate reason to arrest any of these people, they can. But it is unconstitutional for the government to interfere with First Amendment rights on the basis of viewpoint, and that is what appears to be happening. Now a broad coalition of 103 civil liberties and press rights organizations, including many left-leaning groups, are calling on the Department of Homeland Security (DHS) to cease any targeting of Americans for their First Amendment-protected speech.

This is a positive development for any supporter of personal privacy and free speech. Government is often a foe to causes on both sides of the political spectrum, and law enforcement agencies can be just as threatening to privacy and speech rights as big bureaucracies.

In Memphis last year, police were found to have violated a court order by illegally surveilling Black Lives Matter activists. In Washington state, police sought a warrant forcing Facebook to expose information about an environmental group that protested the Dakota Access Pipeline. The police wanted the account names of everyone invited to attend the protest, contact information for the group’s administrators, and all posts and other content tagged on the page.

Whether the victim is a group on the left, right, center, or something else entirely, government tracking of the members and activities of advocacy groups makes it more likely that a corrupt agency or individual will one day wreak havoc on their constitutional rights. The effect, and sometimes even the goal, of this harassment is to impede or altogether stop a group’s activities.

After all, it’s easy to find choke points when you have access to an organization’s every member, event, private chat, or social media post. Or, as the Supreme Court put it more than 60 years ago, “compelled disclosure of affiliation with groups engaged in advocacy may constitute as effective a restraint on freedom of association as [other] forms of governmental action.”

That quote came in a 9-0 decision upholding the NAACP’s right to keep the identities of its members private. Times have changed since that landmark decision, but the need to protect political advocacy from government obstruction never goes away.

‘Transparency’ Rhetoric Used for Dangerous Ends

Unfortunately, states increasingly consider—and sometimes pass—measures to expose supporters of advocacy groups, hidden in the rhetoric of “transparency.” The U.S. House of Representatives passed such a bill on a party-line vote this year as part of the omnibus H.R. 1 legislation broadly regulating campaign finance, voting, and ethics. Elsewhere, powerful state attorneys general are acting unilaterally to demand advocacy groups expose the private information of their supporters.

Often, this highly sensitive information is posted online, where anyone can use it. These actions deter vital speech and activism. Many people will choose not to speak if someone—especially the government—is looking over their shoulder.

Fortunately, we can take steps to enhance our self-governance, protect free speech, and shield privacy all at once. Believe it or not, the Internal Revenue Service has shown the way. It announced last year that it would stop collecting donor names and addresses for many kinds of nonprofits. The agency’s announcement noted that the IRS did not need or use the information, and that it was sometimes leaked.

Government at all levels must stop collecting sensitive information for which it has no legitimate purpose. Legislators must also clarify that advocacy groups have a right to keep their supporters’ private information private. Officials who violate that right should be held accountable.

In an increasingly connected world, the risk of surveillance stifling speech is higher than ever. Protecting First Amendment rights in the 21st century calls for a renewed focus on privacy.