The Bar Association is warning politicians to be careful when criticising the decisions of judges.
Deputy Prime Minister Winston Peters and National leader Simon Bridges have been critical of a judge who granted name suppression to a convicted fraudster.
Joanne Sharp was granted name suppression in 2007 after defrauding Tower Insurance, and subsequently went on to defraud the Ministry of Transport under the name Joanne Harrison.
Her name suppression has now been lifted and politicians are saying it should never have been imposed.
A spokesperson for the Bar Association, Jonathan Eaton QC, said debate about legal decisions was a good thing, but politicians wading in with hindsight assessments were unhelpful and unfair.
When facts changed years later, that did not make the original decision wrong, he said.
Upholding the independence of judges was fundamental, Mr Eaton said.
Harrison stole nearly $750,000 over four years while employed as a senior manager at the Ministry of Transport and was sentenced to three-and-a-half years in prison in February 2017.
Last year, she was denied parole because she posed an undue risk to society.
The Parole Board detailed Harrison's lengthy record of offending - saying she had committed "frauds in 2005, 2007, 2008, 2009, is alleged to have committed fraud in Australia on an employer in 2010, and committed the index [Transport Ministry] frauds from 2012 to 2015".