I am a lawyer in NSW not South Australia, and
I am expressly
not an expert on the law of evidence as it operates in South Australia,
nor on Coronial practice there.
So factor that in when you decide how much notice to take of this reply.
A Coroners Court is a court like any other.
An inquest is a formal court proceeding like any other.
Which means, first above all, that a person giving evidence
has a duty at common law tell the truth, and all of it, and only the truth,
in accordance with the oath they will take as a witness.
In South Australia, there is also a statutory duty to answer questions,
under oath, in a Coronial proceeding.
More particularly,
- If a person lies under oath (including lying by leaving things out,
or by pretending to be unsure, or by pretending to not remember something),
then that can be an offence.
Depending on which is invoked, you could be looking at...
- for evidence given in person (in the witness box),
an offence under section 27 of the Oaths Act 1936 (SA)
(up to four years in prison), or
- for evidence given in writing (eg an affidavit),
an offence under section 20 of the Coroners Act 2003 (SA)
(up to two years in prison).
- If a person does not answer a question in court, or if they continue to
refuse when directed to do so, then they could be looking at an offence of
contempt of court (section 23 of the Coroners Act 2003 (SA),
(a fine of up to $10,000, or up to two years in prison - in theory, without further trial).
Note that this may not be a conclusive list (local SA lawyers will know better than I).
There is one exception - a person is not required to answer a question
in an inquest if doing so would tend to incriminate them (section 23(5)).
However, it would be unwise to think of this as the sort of catch-all
veil to hide behind in the way that American TV makes out their "Fifth Amendment" to be.