The National Park Service is proposing to overhaul regulations related to demonstrations and special events at certain national parks in the capital that could make organizing a protest more expensive.

The proposal, for which the NPS is taking public comments until Monday, could potentially charge protest organizers for certain costs or outlaw protests in front of the White House and at other popular protest locations in D.C., such as the National Mall.

“The idea came out of just the sheer cost to the Park Service and Park Police putting on and supporting some of these events,” Mike Litterst, a spokesman for the agency told the Washington Post. “At this point we’re just asking the question.”

Critics have decried the proposal as an effort to curb free speech. The American Civil Liberties Union released a statement against the proposal, saying “the amendments now proposed harken back to the era in which the courts had to be called upon to protect the right to dissent in the nation’s capital” and said that the “NPS cannot balance its budget on the backs of people seeking to exercise their constitutional rights.”

The 14 changes, first proposed in August, would modify existing regulations on how the NPS processes permit applications for demonstrations and special events. The rule would also identify locations where activities are allowed, not allowed, or allowed but subject to restrictions — which would include limitations on the size of signs, flags, and similar items carried into the area.

The ACLU noted in its statement the proposal’s clause to reduce distinctions between demonstrations and “special events,” which include concerts, weddings, and festivals. Typically, demonstrations have previously received less scrutiny and often get their permits almost automatically. Under the amendments laid down in the proposal, those protections could change, particularly if there is singing or dancing involved in a protest.

The number and size of demonstrations held in the district has increased substantially in recent years, with an average 750 protest permits annually, the Post reported. In 2017, the district had 714 permitted demonstrations, which included the first "Women’s March" that followed the president’s inauguration and brought tens of thousands to the Mall and surrounding streets. Notable protests from this year included the "March for Our Lives" — an anti-gun-violence rally which saw an attendance of hundreds of thousands and was a nationally televised event.

Litterst did not provide the Post with an estimate of costs incurred from protests and demonstrations, but said that the processing of permits alone costs the department $700,000 in staff time annually.

As of Friday, the NPS has already received more than 7,600 comments.