Legal purchase of a sound suppressor in the United States is administered by the Bureau of Alcohol, Tobacco, Firearms and Explosives (BATFE). Before the purchase can be made, the person must undergo the application process, which includes paying a $200 tax and undergoing a criminal background check. Some purchasers are surprised to find that sound suppressors in the US are often very expensive -- in many cases exceeding the cost of the firearm they are to be used with. In some states -- including California, Hawaii, New York, New Jersey, Illinois, and some others -- sound suppressors are completely banned for ordinary citizens. In states that allow suppressors, there may be purchase requirements in addition to those required by the federal government.