The Chief Coroner believes the Auckland District Health Board's failure to return all of a baby's heart to his grieving family is an exceptional case.
Four-day-old Lazariah Mar had some tissue removed during two heart operations, but died following the surgeries.
The family had asked for all of the baby's body to be returned so they could bury him whole. But a month later they received a letter saying the hospital still had some of his heart tissue. The family buried it on Tuesday.
The baby's grandmother, Mere Ngakoti, says it has been distressing for the whole whanau, especially the newborn's parents. She says they have had to grieve all over again and it is something they would never want anyone else to experience.
The DHB has apologised and is reviewing the case.
Chief Coroner Judge Neil MacLean told Morning Report on Thursday that a law change around coronial post-mortems has ensured that families have absolute rights.
But he said the situation for other deaths may not be as clear and he knows that the subject is being discussed by health authorities, police, coroners and others.
Mr MacLean says he is sure that DHBs are aware of the sensitivities around tissue retention.