About the CMC. They can be asked by QPS or AFP to conduct a hearing to ask someone questions about a serious crime that has been committed, where the police believe that person has knowledge that will assist in the prosecution of the crime. The person to be asked the questions wont usually be the suspect themselves. Its a bit like a court hearing, but with important differences.
Its an offence for the person called to answer questions in the CMC not to take the oath or affirmation to tell the truth. Its also an offence for that person not to answer a question, unless they have a reasonable excuse. The only excuse that usually works is that youre a lawyer or a politician who would be breaking parliamentary or legal professional privilege if you answered the question.
If you combine the rules requiring you to take the oath, with the rule about being required to answer questions, then youve got a situation where the person will have to answer a question and if they dont they get fined or imprisoned. If they do answer and lie (and that is found out) then theyll be charged with perjury and go to a real court and either be fined or imprisoned for that offence.
That strategy sometimes works, but for hardcore crims such as bikies, the threat of a year in prison or a fine is of little consequence. Theyll take the punishment rather than spill the beans. You could also have an accomplice or a family member whod take the relatively lighter penalty for perjury than to incriminate the other person.
An important caveat on this compulsion to answer questions though, is that any answer given cant be used in evidence against that person, appearing in the CMC, in a court.
In a real court theres a powerful and essential protection which allows a person to refuse to answer a question if in doing so they would incriminate themselves in some offence. This is based on the principle that a person is innocent until proven guilty and that they dont have to say anything to police. They dont have to prove their innocence, the Crown has to prove their guilt.
Heres a highly hypothetical example. A fellow goes on trial in the Supreme Court for the murder of his wife. A person is subpoenaed to give evidence as a prosecution witness. The witness is told that there is a record of him having had a phone conversation with the accused on the night of the alleged killing. The witness is asked by the prosecutor what the substance of that conversation was. The witness must answer the question, just like in the CMC. But, in the court, unlike in the CMC, the witness can refuse to answer the question on the grounds that in answering it he would incriminate himself in some offence. The conversation could, for example, have been about how to dispose of the body. Answering the question truthfully would implicate the witness in an offence, so he could refuse to answer it on the grounds of the self-incrimination privilege. And if the state believes the witness has committed any offence its up to them to prove it, not for him to admit to it. Like it or loathe it, thats the way the cookie crumbles. All just IMO. MOO.