What happens when the police turn up at the hospital or doctor's reception desk asking to see medical files as part of a criminal investigation?
Health agencies have considerable discretion about releasing your medical history to the police without asking you. The Health Information Privacy Code says it is fine to hand over information, as long as doing so is thought to be necessary to maintain the law "including the prevention, detection, investigation, prosecution and punishment of offences."
If a district health board still decides not to release any information, the police can either get a warrant, or apply under the Official Information Act.
Privacy law specialist Deborah Marshall of law firm Meredith Connell, which advises district health boards and the police, says that unlike privacy law, the Official Information Act emphasises releasing information unless there is a good reason not to.
A district health board would argue privacy is a good reason. "But under the OIA it has to balance private interests and public interest. If the police are investigating something serious it becomes a public interest.
"It's quite a minefield for the agency receiving the request because there are a number of different acts they have to look at," says Marshall.
Of course, you are thinking, if you have not committed any crimes, you have nothing to fear from this.
But what if the police were looking for a burglar whose arm was broken during a scuffle with the home owner and they could go to the local A&E department to look through the files of people who showed up there with broken arms that week?
Police privacy officer Andrew Jack, says the police seldom have a problem accessing medical records.
"We've found we've had a high degree of cooperation from the medical profession and we're keen to enhance that."