Between 1992 and 1996, the
Commission on Presidential Debates changed its rules regarding how candidates could qualify to participate in the presidential debates. As Perot had previously done very well in debates, it was a decisive blow to the campaign when the Commission ruled that he could not participate on basis of somewhat vague criteria --- such as that a candidate was required to have already been endorsed by "a substantial number of major news organizations", with "substantial" being a number to be decided by the Commission on a case-by-case basis. Perot could not have qualified for the debates in 1992 under these rules, and was able to show that various famous US Presidents would likewise have been excluded from modern debate by the Commission on Presidential Debates.
Despite legal action by the Perot team, and an 80% majority of Americans supporting his participation in the debates, the Commission refused to budge and Perot was reduced to making his points heard via a series of half-hour "commercials". In the end, Perot and Choate won 8% of the vote.