A Brisbane judge who sentenced a father of two to jail for contempt of court in a family law case has been sharply criticised by Family Court appeal judges, who described his decision as an "affront to justice".

Key points: Judge Salvatore Vasta had no power to jail a man for contempt, the Family Court declared

Judge Salvatore Vasta had no power to jail a man for contempt, the Family Court declared Three Family Court judges called the man's imprisonment "a gross miscarriage of justice"

Three Family Court judges called the man's imprisonment "a gross miscarriage of justice" They said Judge Vasta had "no factual foundation" for the order

Last December, Brisbane-based Judge Salvatore Vasta sentenced a man involved in a property dispute with his ex-wife to a maximum 12 months in jail for failing to disclose financial documents on time.

The man, who has two children aged five and nine, spent six days in a maximum-security prison.

He was released pending the outcome of an appeal on the decision.

In a ruling handed down earlier this month, the Full Court of the Family Court overruled Judge Vasta's decision, with justices Peter Murphy, Michael Kent and Steven Strickland declaring they were comfortably satisfied that "what occurred here in the making of the declaration and order for the husband's imprisonment constituted a gross miscarriage of justice".

"We are driven to conclude that the processes employed by the primary judge were so devoid of procedural fairness to the husband, and the reasons for judgment so lacking in engagement with the issues of fact and law to be applied, that to permit the declaration and order for imprisonment to stand would be an affront to justice," they stated in their ruling.

Judge Vasta's ruling was also roundly condemned by the Law Council of Australia.

"The Law Council is gravely concerned by the conduct of the Federal Circuit Court judge in this matter and the devastating impact of this case on both the unrepresented parties and their young children," Law Council president Arthur Moses said.

"As outlined by the Full Court, the judge's conduct was simply unacceptable.

"This case reinforces the fact that not only the outcome of a case but the very way in which family law matters are handled by the courts has direct, life-altering and irreversible consequences for the children and families concerned."

Judge Vasta has been approached for comment.

'That's what I do'

During the initial court hearing, Judge Vasta told the man that if he did not hand over the required documents on time, he should "bring your toothbrush".

"If there isn't the full disclosure there will be consequences, because that's what I do," Judge Vasta told the man.

"If people don't comply with my orders there's only one place they go … I don't have any hesitation in jailing people for not complying with my orders."

But the Family Court judges determined Judge Vasta had "no factual foundation" for the order to imprison the man and he had no legal power to do so.

During the proceedings, the man's wife told Judge Vasta she did not want her former husband to go to jail.

She told Judge Vasta that "we have kids together that I have to think about as well, that this affects the kids of the rest of their lives".

Court merger concerns

Chief Justice John Pascoe said family law had become increasingly complex. ( Supplied: Family Court of Australia )

Last year, Attorney-General Christian Porter announced plans to merge the Family Court and the Federal Circuit Court, promising it would ease the significant delays and costs for people stuck in the system.

The Australian Law Reform Commission (ALRC) is conducting a wide-ranging review of the system, which is due to be handed to the Federal Government next month.

Many lawyers have been critical of Mr Porter's merger proposal, which would be the most significant shake-up of the sector since it was established in the 1970s, arguing any changes should wait until the ALRC delivers its findings.

Last October, Family Court Chief Justice John Pascoe told a law conference in Brisbane that family law had become increasingly complex.

"In my view, if legislation and the ALRC report do not assuage public concerns about the family law system, it must surely be time to consider a royal commission into family law," Justice Pascoe said.