If you were to look up the word Convict you will find that an overwhelming number of dictionaries give the definition as
Convict 1. Declare (someone) to be guilty of a criminal offence by the verdict of a jury or the decision of a judge in a court of law.
Convict 1. Law To find or prove (someone) guilty of an offense or crime, especially by the verdict of a court:
con•vict verb (used with object)
1.to prove or declare guilty of an offense, especially after a legal trial: to convict a prisoner of a felony.
2. to impress with a sense of guilt.
Why it matters [and how it applies to the John Banks case]
The seat of any member of Parliament shall become vacant—d) if he or she is convicted of an offence punishable by imprisonment for life or by 2 or more years’ imprisonment or is convicted of a corrupt practice, or is reported by the High Court in its report on the trial of an election petition to have been proved guilty of a corrupt practice;
The offence with which Banks was charged is an offence punishable with imprisonment of 2 years .
It is interesting that currently our legislation does not have a definition for convicted but up until 1 July 2013 the crimes act 1961 carried such a definition which was repealed on that date this definition read.
3. Meaning of “convicted on indictment’‘—For the purposes of this Act, a person shall be deemed to be convicted on indictment if—
(a) He pleads guilty on indictment; or
(b) He is found guilty on indictment; or
(c) He is committed to the Supreme Court for sentence under section 44 or section [153A or section] 168 of the Summary Proceedings Act 1957; or
(d) After having been committed to the Supreme Court for trial, he pleads guilty under section 321 of this Act.
I have no idea why this was removed from the legislation 1 July 2013, by section 6 of the Crimes Amendment Act (No 4) 2011 (2011 No 85). But it appears that a huge hole was left in the legislation
The scenario used to be convicted – sentenced.
Now it appears to be found guilty – convicted – sentenced.. Yet there appears to be no legal precedent or legal foundation for this.
The interpretation act gives no definition for convicted or guilty.
Since our legislation no longer defines Convicted we have to rely on the interpretation of the legislation and the common dictionary meaning
There are many examples in legislation which point to the fact that convicted still means guilty e.g.
Criminal Procedure Act 2011 section 147
4) Without limiting subsection (1), the court may dismiss a charge if—
• (a) the prosecutor has not offered evidence at trial; or
• (b) in relation to a charge for which the trial procedure is the Judge-alone procedure, the court is satisfied that there is no case to answer; or
• (c) in relation to a charge to be tried, or being tried, by a jury, the Judge is satisfied that, as a matter of law, a properly directed jury could not reasonably convict the defendant.
So how could a jury convict any one if this is something that is only in the realm of a judge and done after being found guilty?
The reality is that this makes sense only if to convict and to find guilty are one and the same thing.
The plot thickens when you read the judgement R v BANKS  Paragraph 6
 The information against Mr Banks was laid on 10 December 2012. Sections 105 and 106 of the Criminal Procedure Act 2011 apply to Judge-alone trials. However, those provisions only came into force on 1 July 2013. Pursuant to s 397 of the Act, this matter has been determined in accordance with the law as it was before that date.
The Crimes Act definition of “convicted” still existed at that time as it was not repealed until 1 July 2013
The criteria for section 3 crimes act Print/Download PDF (5.5MB)or see it on it own Crimes Act 1961 S 3 are therefore the criteria which apply to this decision and he question is was he found guilty on indictment.
The answers to that are again in the decision
 The indictment reads as follows…
 I have found Mr Banks guilty of the charge
The only possible outcome in that case is that John Archibald banks is convicted
We will keep you posted.
Perhaps the government in the meantime would like to attend to the definition of Convicted.