The family of a 91-year-old man with dementia who was killed by a train after wandering onto railway tracks argued Tuesday before the Supreme Court that holding them liable for disrupting train services would essentially deny that healthy and disabled people can coexist in society.

The case will be the first time the nation's top court rules on the liability of families of dementia patients. The decision is expected to be handed down March 1.

Traditionally, when the Supreme Court holds a hearing, a high court ruling is usually overturned. This means the top court is likely to issue a different ruling than the Nagoya High Court, which held the dementia patient's wife liable in 2014.