Anti-corruption watchdog Transparency International (TI) on Tuesday published a report showing Spain and Syria dropped the most in a ranking of countries and regions by their perceived levels of public sector corruption.
Out of 177 countries and regions, Spain came in 40th behind counties such as Cyprus and Portugal.
Spain found itself falling further behind northern European countries and at risk of losing ground to countries such as Greece and Italy, which have "in the last year created laws and anti-corruption systems which are strong and modern and which have sent out a positive message," according to TI representative Alejandro Salas.
In contrast Spain "has seen scandal after scandal," he added.
Spain has been hit by a series of high-profile corruption scandals in the past year.
For example, the former mayor of Castellon Carlos Fabra was last week sentenced to four years in prison for fraud amounting to 700,000 euros (950,000 U.S. dollars). Fabra was the driving force behind Castellon airport, constructed at a cost of around 150 million euros in 2011 and which has never received a commercial flight.
The airport is adorned with a statue of Fabra, thought to have cost over 300,000 euros.
Salas said the ongoing corruption cases point to a "structural weaknesses" in the Spanish legal system and a lack of public confidence over issues such as the granting of contracts for public works.
TI said Spain's new transparency law was "weak" and "lacks clear punishment", given that it relies much on the discretion of civil servants." (1 U.S. dollar = 0.74 euro)