The Sydney silk who helped put Eddie Obeid behind bars has denied the former MP was the victim of a miscarriage of justice and said his defence lawyers acted strategically by keeping material from the jury that would have "come very close to guaranteeing his conviction".

Obeid, 73, was jailed in December for a maximum of five years after a Supreme Court jury found him guilty of misconduct in public office over his family's secret business dealings at Circular Quay.

The former NSW Labor minister is appealing against his conviction and sentence in the Court of Criminal Appeal, which concluded a three-day hearing on Wednesday.

Obeid's lawyers have argued he should not have stood trial in any court because breaches of the code of conduct governing NSW MPs are within the "exclusive cognisance" or jurisdiction of Parliament, rather than the courts.

But Peter Neil, SC, who prosecuted Obeid, told the Court of Criminal Appeal that the Crown did not rely on a breach of the code as part of its case against the former minister.

The way the trial was conducted "gives rise to no miscarriage of justice", Mr Neil said.

Mr Neil said Obeid's legal team did not raise the code of conduct during the trial because it would have been "too dangerous" and it "would have come very close to guaranteeing his conviction".

His lawyers made a strategic decision "not to put Mr Obeid's neck in the noose of the code at the trial", Mr Neil said.

The code refers to ministers' duties to act with honesty and integrity "to advance the common good of the people of NSW".

"You might as well plead guilty," Mr Neil said.

But Guy Reynolds, SC, for Obeid, said the Crown had run a "vigorous" case against the former MP and if referring to the code of conduct would have "guaranteed" his conviction the court could "rest assured" it would have done so.

Mr Reynolds has told the court there is nothing in the code of conduct that would have required Obeid to disclose his family's interest in two cafes at Circular Quay when lobbying a senior maritime bureaucrat.

NSW Solicitor-General Michael Sexton, SC, appearing for Attorney-General Mark Speakman, told the court that "ordinary crimes" could be dealt with by both Parliament and the courts and this was not a case in which Obeid's conduct fell within the exclusive jurisdiction of Parliament.

He added that "there must be a question here" about whether Parliament would have jurisdiction over a former member of the NSW upper house in any case.

Obeid was not charged with misconduct in public office until well after he quit politics in 2011.

A five-judge bench of the Court of Criminal Appeal reserved its decision.

Obeid's wife Judith and son Moses attended each day of the appeal to support the family patriarch, along with members of their extended family.

Obeid and Moses are facing a new trial with former NSW Labor minister Ian Macdonald over an alleged coal deal involving the Obeid family's rural property at Mount Penny in the Bylong Valley.

The men will enter their pleas in the District Court on Friday.