I keep an eye on news regarding this topic just to see if justice will be served. While finding nothing yet, I did see this article on clean-up:
Graffiti Cleanup in National Parks Proves Challenging"Removing the unwanted images without causing further damage is a delicate task, as chemical solvents and sandblasting can potentially strip away more than just the paint, affecting the underlying stone, geologically important micro-fossils, or nearby ancient rock art. Workers are carefully testing chemicals to make sure they are safe to use, then applying them in a stream of low-pressure hot water. Plastic kitchen spatulas are being used to carefully scrape off the acrylic paint, layer by layer."
Investigation continues...
Woman paints faces defacing 8 national parks including Zion, Canyonlands"Investigators continue to collect evidence, conduct interviews and are consulting with the U.S. Attorney’s Office about potential charges. They ask the public to exercise patience and allow due process to take its course as the investigation moves forward, according to a statement written by National Park Service spokesman Jeffrey G. Olson."