manslaughter,homicide committed without justification or excuse but distinguished from murder by the absence of the element of malice aforethought. Modern criminal statutes usually divide it into degrees, the most common distinction being between voluntary and involuntary manslaughter. Voluntary manslaughter is a killing done in the heat of passion provoked by acts of the victim such as to cause a reasonable man to act rashly and without reflection. Such provocation may include violent assault and an unlawful attempt to arrest him, but not mere insulting words or gestures. Involuntary manslaughter is a killing in which there is no intention to kill at all. It occurs when the killing is the result of the commission of a crime that is neither a felony nor an act likely to cause great bodily harm or when it is the result of a lawful act done in a criminal manner, e.g., a case of negligence. The advent of the automobile caused many manslaughter cases that arise from reckless and careless driving; in the statutes of some states of the United States such killing is a separate crime.