Red caps bearing the slogan became prominent during Donald Trump’s presidential campaign in the United States in 2016.
They have continued to be worn by supporters of the former president — including by members of the American Proud Boys, which New Zealand designated as a terrorist organisation in June this year.
In a statement, St John assistant clinical director Kris Gagliardi said several internal training videos were filmed in 2017, "against a backdrop of items that were associated with pop culture that year".
"At the time staff who arranged the setup did not appreciate the symbolism of the item and the offence it causes," Mr Gagliardi said.
The symbolism associated with the hat did not "in any way" align with St John’s values, and the organisation apologised for its inclusion in the video.
Concerns were raised when the video was released and were taken "very seriously" by management.
The video was taken down and republished with the hat blurred out.
St John was unaware until alerted that an original copy of the video still existed and had directed staff to re-check all video podcasts to make sure none still contained the item, Mr Gagliardi said.
The apology came after a screenshot of the uncensored video was posted on Twitter.
Former leader of the National Party Todd Muller drew criticism in 2020 for displaying a similar cap in his office.
At the time, Aliya Danzeisen of the Islamic Women’s Council said the hat represented the denial of freedom of belief and minority voices.
"That hat represents the vitriol that has been harming that nation and has been harming the world for the last four years," she said. — Additional reporting The New Zealand Herald