Worksafe NZ is investigating allegations of bullying at Auckland Hospital morgues.
An anti-bullying advocate, Allan Halse, said he had laid complaints with the Employment Relations Authority on behalf of two mortuary workers.
Mr Halse said the complainants were picked on by a senior staff member and then ostracised by the rest of the workers when they spoke out.
He said one woman felt so isolated she spent most lunch breaks in her car crying.
Mr Halse said the Auckland District Health Board did nothing to help them and when they spoke out the problem became worse.
"To start with they were only picked on by individuals and specific colleagues, but if they raise a complaint within the organisation basically the whole group turned on them."
The Auckland District Health Board said it could not comment on what it called "unsubstantiated hearsay" for legal reasons.
In a statement, it said it stands by the clinical expertise of its staff and the respectful way they care for bodies.