A New Zealand professor had trouble entering Australia because of a conviction she got opposing the Springbok tour in the 1980s.
Professor Jane Kelsey said she was detained at immigration at Sydney airport on Sunday and told she did could not enter visa free like most New Zealanders because she was not an "appropriate person" under Australia's 1994 immigration laws.
Eventually she was allowed to enter but was told in future she would need a visa.
"I am a constant visitor to Australia for professional and personal reasons - at least eight times in the past two years, including just one month ago for an academic conference on trade," Prof Kelsey said.
"I always tick the box about criminal convictions, which relate to the Springbok tour and Bastion Point in the early 1980s. They have the list on record at Australian immigration. Usually I wait 10 or at most 15 minutes and they wave me on. This twist came completely out of the blue."
She has complained to the Australian High Commissioner.
"It is possible it is an ill-judged over-reach by super-officious immigration officials at Sydney," she said.
"However it is equally likely that my name has recently been flagged, presumably linked to my role in promoting critical debate on the TransPacific Partnership negotiations. Requiring me to apply for a visa each time I go to Australia would make it easier to monitor and restrict my movements. At the very least it sends an intimidating message to me and to others."
Prof Kelsey previously said the SIS was keeping tabs on her because of her criticism of neo-liberalism and free trade agreements.
She is visiting Australia to promote a new book on the Trans-Pacific Partnership Agreement.
Australia's Department of Immigration and Citizenship National Communications Branch said it would not discuss an individual's visa status.
"But generally speaking, if a New Zealand citizen has criminal convictions, there are instances where they will be ineligible for the default special category visa (and, in more serious cases, they may fail the character requirement altogether and be unable to secure a visa to Australia)."
The spokesperson said New Zealanders with health problems or criminal histories needed to check with their local Australian Immigration office before travelling there.
"What can happen in a set of circumstances such as these where a special category visa is not appropriate because of criminal convictions, the immigration officer has the discretion to grant a border visa allowing entry rather than refusing entry and returning the person on the next available flight. The passenger will be counselled that next time they need to approach an Australian Immigration office first or risk being turned around at the border."