Criminal mischief (sometimes termed malicious mischief) is willful destruction of the property of another.
This offense requires an actual human action observable to a bystander, and tangible damage to property. In computer-related crime situations, a distinction must be made between damage to computer hardware and damage to software.
Hardware damage can be measured and appraised in traditional ways, but software, though tampered with, may appear undamaged or actually be unchanged. For example, a programmer could conceivably program a computer to override or erase the program's error detection keys, thus employing the computer as an agent in the crime. The damage could be delayed until the proper sequence of keys caused the computer to "remember" its instructions to override or erase.
Most States that recognize this crime provide for classes of the offense, depending on the value of the damage done to the property. Though such criminal mischief statutes may have applicability in prosecuting attacks against computer hardware, problems exist in using such a law to prosecute malicious attacks against software if electronic impulses and software programs have not been accepted as "writing" or "property" in the relevant jurisdiction.