Spain's government is being taken to court over a minister's decision to give the country's top policing award to a statue of the Virgin Mary.

The country's interior minister, Jorge Fernández Díaz, singled out an icon of the Virgin Mary, in Málaga, to receive the gold medal of police merit – which is normally reserved for police who have died in terrorist attacks.

Announcing the award in February, Díaz lauded the Virgin and her congregation for "maintaining a close collaboration with police, particularly during the acts celebrated in Holy Week, and for sharing police values such as dedication, caring, solidarity and sacrifice".

The award has infuriated secularists, who are demanding the medal be revoked, given that the Virgin and her congregation had "failed" to meet any of the minimum requirements.

"The norm specifies clearly that the medal is given to people not immaterial beings," said Francisco Delgado, of Secular Europe. "It's meant to recognise exceptional acts of service by police."

His group has joined forces with the Movement Towards A Secular State (Movimiento hacia un estado laico) to bring the interior minister to court. The case will be heard in June.

Although Spain's 1978 constitution enshrines the separation of church and state, the boundary between the two remains blurred, said Delgado, whose organisation was created in 2001 by a group of professors dismayed at the slow pace of Spain's transition to secularism.

"There are still so many ties to the church that Spain has never got rid of. The Spanish state still provides millions of euros a year to the Catholic church, there are Catholic schools financed heavily by the state."

This year the interior minister was taken to task by the opposition for saying that Saint Teresa was "making important intercessions" for Spain "during these tough times".

The Virgin Mary, in Málaga, is not the only Virgin to have been recognised by the minister. In 2012, the Guardia Civil's highest honour was granted to Zaragoza's Virgin of Pillar, the institution's patron saint. In the decree, Díaz said the award paid tribute to the "deep roots of the patronage of the Virgin of Pillar, which remains part of the heritage of the Guardia Civil".

Still, the medal awarded in February caught the national police by surprise.

José María Benito, from the police officers' union, told the online daily El Boletín: "Give the Virgin whatever you like, take her some flowers, make her the patron saint of our people, but don't give her a police medal, least of all one reserved for police officers who have lost their lives in an attack."As the government muddies the line between church and state, Delgado's group has consistently lodged complaints. However they had shied away from court action until now, said Delgado. "The little separation between political and judicial power in Spain means that the justice system often sides with politicians."

This time the clear-cut nature of this case emboldened them to take the risk, he said. "We thought it time the courts pronounced on these acts that seem to be more from the 18th century than the 21st." The case will be heard in June.