Foreign interference in U.S. politics has been in the news lately, and the controversy affects nonprofits in one important way.

Congressional efforts are under way to step up application of the Foreign Agents Registration Act (FARA)—a law enacted in 1938 amid war and rumors of war to counter pro-German propaganda. Its broader purpose was to inform the American public about foreign attempts to influence public opinion and policy.

FARA requires U.S. persons and organizations that engage in certain activities on behalf of foreign entities to register with, and report regularly to, the Department of Justice. The law specifies five types of activities: political, public relations, political consulting, publicity, and information services.

FARA defines “foreign agent” broadly. That makes the law hard to enforce and has been rarely invoked. If enforcement proceeds now without further guidance, the law’s ambiguities will pose a challenge to nonprofits trying to determine their standing.

For example: A Dutch group drafts a policy paper addressing environmental damage and asks a U.S. nonprofit to organize a public forum or a session at a conference to discuss it. Because the nonprofit is acting at the behest of a “foreign principal,” does that make it a foreign agent? According to the letter of the FARA law, it does.

The law provides some exemptions, including academic, religious, and certain charitable activities.

But if your nonprofit fits FARA’s definition, you’ll have to register with the Department of Justice as a foreign agent. You’ll also need to submit semiannual reports about your activities. And noncompliance can bring criminal penalties.

Some organizations may drop international activities and collaboration rather than face the burdens of registration and reporting. Others will need a careful and detailed review of their activities along with FARA’s provisions.