"Three German tourists have been accused of defacing various parts of Joshua Tree National Park last weekend, adding to the California destination’s ongoing battle with vandalism.
On August 4, a ranger patrolling the popular Jumbo Rocks Campground noticed “fresh” yellow paint splattered all over park infrastructure, according to a news release from the National Park Service. After more rangers were called to investigate the area, NPS said they found and questioned a group of tourists who admitted to shooting paint with paintball markers and slingshots. Both are considered weapons and prohibited in the area. When rangers searched the visitor's car, they discovered three slingshots, a paintball marker and other equipment.
At least 11 signs along Park Boulevard from Jumbo Rocks campground to the Maze Trailhead were defaced, the release said. Each person received a violation notice for firing paintballs on signs, bathrooms and dumpsters, which could lead to a maximum fine of $5,000 and up to six months in prison. "
That's pretty shitty but it was just signs (not Joshua trees or rocks) and that paint is water based and should come off with a pressure washer.