He said the union members wanted to get the public on side, but would not rule out industrial action.
Kerr said the transport officers would be all over the network and not necessarily on trains doing critical safety jobs like getting people on and off trains and providing first aid.
"This idea of transport officers is a sop. There is no question in our minds that getting rid of train managers (guards) is a cost-cutting exercise at the expense of public safety," Kerr said.
In a statement, Auckland Transport said the combination of on-board transport officers and more electronic gates at rail stations will reduce vandalism, fare evasion and create a better experience for commuters.
Transport officers will operate on 24/7 shifts and be able to be deployed to where and when they are most needed, the statement said.
Meanwhile, police are still making inquiries in the case of a violent and sexual assault by five men dressed in costumes on a train from Britomart to Avondale on August 12.
A man has been arrested after allegedly indecently exposing himself to two teenagers on the train. The man was charged with indecent exposure and will appear in Auckland District Court on September 7.