José Luis Rodríguez Zapatero spearheaded landmark social reforms during a seven-year premiership that endeared him to the Spanish left - but recent suspicions of corruption have tarnished his once spotless reputation.
The Socialist titan, who governed Spain from 2004 to 2011, was an asset for a party currently grappling with a series of scandals that have damaged its popularity ahead of a general election expected in 2027.
"What matters in life? Trying to help others, living together, showing solidarity, caring about those suffering discrimination, about those who suffer the most, the weak. That is what lets you breathe easy," Zapatero told a Socialist rally in May.
A few days later, the 65-year-old former constitutional law professor became the first serving or former Spanish prime minister to be placed under formal legal investigation.
The case centres on the €53-million ($61.5 million) state bailout of small airline Plus Ultra in 2021, and whether Zapatero used his influence to secure the money in exchange for commissions.
