2003 Castilian-Manchegan regional election

The Cortes of Castilla–La Mancha were the devolved, unicameral legislature of the autonomous community of Castilla–La Mancha, having legislative power in regional matters as defined by the Spanish Constitution and the Castilian-Manchegan Statute of Autonomy, as well as the ability to vote confidence in or withdraw it from a President of the Junta of Communities.[2] Voting for the Cortes was on the basis of universal suffrage, which comprised all nationals over eighteen, registered in Castilla–La Mancha and in full enjoyment of their political rights.

The 47 members of the Cortes of Castilla–La Mancha were elected using the D'Hondt method and a closed list proportional representation, with a threshold of 3 percent of valid votes—which included blank ballots—being applied in each constituency. Parties not reaching the threshold were not taken into consideration for seat distribution. Additionally, the use of the D'Hondt method might result in an effective threshold over three percent, depending on the district magnitude.[3] Seats were allocated to constituencies, corresponding to the provinces of Albacete, Ciudad Real, Cuenca, Guadalajara and Toledo. Each constituency was allocated a fixed number of seats: 10 for Albacete, 11 for Ciudad Real, 8 for Cuenca, 7 for Guadalajara and 11 for Toledo.[2][4]

The electoral law provided that parties, federations, coalitions and groupings of electors were allowed to present lists of candidates. However, groupings of electors were required to secure the signature of at least 1 percent of the electors registered in the constituency for which they sought election. Electors were barred from signing for more than one list of candidates. Concurrently, parties and federations intending to enter in coalition to take part jointly at an election were required to inform the relevant Electoral Commission within ten days of the election being called.[4][5][6]

The term of the Cortes of Castilla–La Mancha expired four years after the date of their previous election. Elections to the Cortes were fixed for the fourth Sunday of May every four years. The previous election was held on 13 June 1999, setting the election date for the Cortes on Sunday, 25 May 2003.[2][4][5][6]

The President of the Junta of Communities had the prerogative to dissolve the Cortes of Castilla–La Mancha and call a snap election, provided that no motion of no confidence was in process, no nationwide election was due and some time requirements were met: namely, that dissolution did not occur either during the first legislative session or within the legislature's last year ahead of its scheduled expiry, nor before one year had elapsed since a previous dissolution. Any snap election held as a result of these circumstances would not alter the period to the next ordinary election, with elected deputies merely serving out what remained of their four-year terms. In the event of an investiture process failing to elect a regional President within a two-month period from the first ballot, the candidate from the party with the highest number of seats was to be deemed automatically elected.[2]