Laser pointers are amazing, particularly for the easily amused. The limits to their uses are generally only limited by a person's imagination, and of course, state and federal law.
By now, most everyone knows that there are laws against shining laser pointers at planes, or shining them in peoples' eyes. However, most people don't realize how illegal it is to shine a laser pointer at an aircraft. It is very illegal (no, "very illegal" is not a technical term). Just last week, a 23-year-old Missouri man was sentenced in federal court to 3 years in prison for the federal crime of pointing his laser pointer at a police helicopter, which is a felony.
Federal and State Laws on Laser Pointers
The easily-amused Missouri man is not alone in his crime; there have been quite a few arrests for laser pointer violations that have garnered just as much publicity. While the devices are fun to play with, people really need to be aware of the dangers, as not everyone will be as fortunate as Clark Gable's grandson, or this California high-schooler.
There is essentially no prohibition on owning lasers of any power for adults. Some states restrict the rights of minors to own lasers with more than a power rating of 1 or 5mW (milliwatt). However, state and federal laws only prohibit certain uses for for a laser, or laser pointer.
Basically, everywhere in the US, shining a beam of light onto aircrafts, or really any vehicles with drivers of any kind, is illegal. Also, there are state specific laws that prohibit shining a laser pointer at law enforcement officers, government officials, or nearly anyone for that matter. However, the laws do vary from state to state, and in severity.
For example, the federal law against shining a laser at an aircraft is a felony, punishable by up to 5 years and $250,000 in fines, while doing the same thing under California law is only a misdemeanor, punishable by up to 1 year in jail and $1,000 in fines.