The public has been misled about the history of the present New Zealand flag, according to NZ Flag Institute executive director John Cox.
Governor Bowen formally authorised the flag for use by Government ships by gazette on October 23,1869. From 1869 the flag was increasingly flown on shore and by the public. It was accepted as the national flag.
In 1902 the flag was formally adopted by Parliament as the national flag for all purposes.
"The current flag has therefore been our flag since 1869, not 1902," Mr Cox says.
"All of the publicity material produced by the Flag Consideration Panel refers to the flag having been adopted in 1902. Virtually nowhere is there even a reference to 1869. The public has been misled about the history of our flag."
Mr Cox says the Flag Consideration Panel published one substantial information booklet, the 150-page New Zealand flag facts.
"This was written by Malcolm Mulholland, a well-known advocate of a new flag, and the only member of the panel with any knowledge of flags," Mr Cox says.
"The booklet is heavily biased in favour of a new flag. The panel has not published any equivalent material in favour of the current flag."
Mr Cox said the NZ Flag Institute, established in 2004 to promote the flag, believed the flag referendum process had been undermined by inaccurate and biased information.