"Police are aware that they have aligned themselves to the International Outlaws MC, which have had their roots in America since 1935," he said.
"Hawke's Bay police regularly speak with the Napier Outlaws MC and we understand that there are no plans for changes or expansion of members and will be monitoring the situation."
He added there hadn't been a growth of motorcycle gangs in Hawke's Bay but that such gangs had always been involved in criminal activity to varying degrees and police monitored them accordingly.
Originally formed in Illinois, US, in 1935, the gang have become recognisable around the world for their "skull and cross bones" back patch, with the bones depicted as pistons.
Dr Gilbert wrote that the symbol, known as "Charlie", was adopted by the club after a similar back patch was made famous by the Marlon Brando film The Wild One in 1954. He said the establishment of the AOA further highlighted the outlaw motorcycle scene's growth in New Zealand.
Plans for a supporter club in Auckland named Black and White 15, which derived from O, for outlaw, being the alphabet's 15th letter, were also under way.
"The beginning of this upsurge was signalled by the arrival of Australia's biggest outlaw club, the Rebels, in 2010 and since then several new groups have formed," Dr Gilbert said.