The Ibrox club said they would "firmly deny any breach of Scottish FA rules" after former Ibrox defender Brown called a refereeing decision "corrupt" on Rangers TV.
In the final match of Rangers' league season, Nicolas Raskin appeared to bundle the ball over the line, with the SFA's key match incident panel later ruling the goal should have stood.
Citing being found in breach of SFA disciplinary rule 38, Rangers said: "If this is now the standard, they will be watched closely to ensure it is applied across the board, consistently, without exception and without favour."
Referee Nick Walsh and his on-field officials thought the ball had been kept out by Hibernian defender Rocky Bushiri, and VAR Andrew Dallas ruled that there was no camera angle that proved Raskin's effort had gone in.
Hibs equalised through Kieron Bowie moments later, with the match finishing 2-2.
Brown said on the club's in-house TV channel: "I would say it is corrupt."
Commentator Tom Miller replied: "Well, I'm not sure we can actually say that." However, Brown added: "Well, I am saying it."
Rangers subsequently demanded the introduction of goal-line technology.
"John Brown spoke emotionally and spontaneously as someone who cares deeply about the club. His words were not scripted, and they were not an official club comment," Rangers said.