However, Plunket's comments did not breach broadcasting standards, it ruled.
Catton was "powerfully exercising her right to freedom of expression and has had to suffer the responses including those from the broadcaster", the BSA said.
"Conversely, the broadcaster has exercised its right to freedom of expression and it will have suffered consequences from those who objected to what Mr Plunket said and the way in which he said it."
The decision from the authority considered that "?different views have been expressed and have been evaluated and those who have expressed or broadcast these views have been judged accordingly".
"This is how we think things are meant to work in a liberal democracy.
"We do not think that our society would be better off if views such as those of the radio host were staunched."
The comments Plunket made were within the expectations of talkback radio listeners, the BSA said.
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