[1] Voting for the Assembly was on the basis of universal suffrage, which comprised all nationals over 18 years of age, registered in the Community of Madrid and in full enjoyment of their political rights.

All members of the Assembly of Madrid were elected using the D'Hondt method and a closed list proportional representation, with an electoral threshold of five percent of valid votes—which included blank ballots—being applied regionally.

In the 1999 election, the PP, under Alberto Ruiz-Gallardón, managed to maintain their absolute majority, despite the opposition PSOE recovering lost ground.

For the 2003 election, the ruling PP had switched leadership: President Ruiz-Gallardón ran as candidate for the office of Mayor of Madrid, while senator and former minister Esperanza Aguirre was selected to lead the regional list.

This sparked criticism from some sectors in the Socialist party, but then-leader Rafael Simancas dismissed them as moot, saying "it was time for a government of the left in Madrid".

However, when the opening session of the new legislature began and the temporary president[8] called for the election of the Speaker to start, concern spread through the Socialist ranks: two of their Assembly Members (AMs) were missing,[9] leaving the left-wing coalition with 54 seats against the 55-strong People's Party.

The scandal swept into the media, making the two "absent" AMs, Eduardo Tamayo and María Teresa Sáez, the most sought-after people in Madrid that day.

Suddenly, they granted a TV interview in which they explained their reasons for not showing up: the coalition deal with United Left, they insisted, was not fair to the voters, who had chosen the Socialists over IU more than five to one.

Tamayo argued that "90% of the PSOE programme is irreconcilable with that of IU"[12] Furthermore, both felt their concerns were too quickly dismissed they were raised in the internal party apparatus, which they criticised as being too willing to reach power no matter what the cost.

He then fired a full round towards the PP, which he accused of bribing the two AMs to prevent a left-wing government in Madrid and "using paychecks to change the election results".

The People's Party was rumoured to be planning an investiture vote for its candidate Esperanza Aguirre, who called for the dissolution of the Assembly and fresh elections.

In response, the two AMs notified the Speaker they would finally enter the Assembly at its next meeting,[16] which created an even more awkward situation: there was no viable majority, since the Socialist party had expelled them, denounced them as "traitors" and refused to accept their votes in an investiture session.

[16] Then, Assembly Speaker, PP AM Concepción Dancausa announced that she would be forced to call new elections if no candidate could heed the confidence of the House.

In a bid to delay the new elections until after the summer, Socialist leader Rafael Simancas, who had pushed for a parliamentary investigation of the events, requested a vote for his investiture to be scheduled.

The latter choice was finally implemented[20] and, after a month of 12-hour sessions in which many prominent politicians and businessmen from both sides were summoned and vast amounts of vitriol were served by both mainstream parties, the committee passed a report concluding Tamayo and Sáez were not bribed by PP and placing full blame on the PSOE.