Casualty insurance is mainly liability coverage of an individual or organization for negligent acts or omissions.
In its most basic form, automobile insurance provides liability coverage in the event that a driver is found "at fault" in an accident.
This can cover medical expenses of individuals involved in the accident as well as restitution or repair of damaged property, all of which would fall into the realm of casualty insurance coverage.
In 1956, in the preface to the fourth edition of Casualty Insurance Clarence A. Kulp wrote:Broadly speaking, it may be defined as a list of individual insurances, usually written in a separate policy, in three broad categories: third party or liability, disability or accident, and health, material damage.
When the NAIC approved multiple underwriting in 1946, casualty insurance was defined as a blanket term for the legal liability except for marine, disability and medical care, and some damage to physical property.