Spanish King Felipe VI's sister Cristina appealed on Wednesday against tax and money-laundering charges that threaten to land her in an unprecedented criminal trial.
If Cristina ends up in the dock, it would be a first for a direct relative of a Spanish monarch and a big headache for Felipe who took the throne on June 19 promising an "honest and transparent monarchy".
Lawyers for the 49-year-old princess sought to overturn the June 25 ruling by investigating judge Jose Castro, which upheld tax fraud and money-laundering charges against her -- a penultimate step towards a possible trial.
In a written appeal, they called on the court on the island of Mallorca to shelve the case, saying there was a lack of evidence and hinting that investigators were out to get the princess.
"Not one procedure has been carried out that has provided rational indications that a tax crime or money-laundering was committed by our client," the lawyers wrote.
"The intention to maintain the charges at all costs seems to have more weight than the strict application of the law."
Castro accused Cristina of knowingly benefiting from suspect business dealings by her husband, former Olympic handball player Inaki Urdangarin, 46, who is himself accused of embezzlement.
A final decision on whether the case goes to trial must be taken by a provincial court in Palma after appeals are heard.
Cristina's lawyer, Miquel Roca, told journalists in Barcelona that he was convinced of her innocence.
"It is not a problem of optimism or pessimism, it is a question of absolute conviction of the innocence of our client," Roca said shortly before submitting the appeal.
"We are convinced that the court will resolve this in a manner that we believe to be appropriate. But we will see."
- 'Sly manoeuvre' -
The investigating judge is at odds not only with Cristina's defence team but also public prosecutor Pedro Horrach, who filed an appeal last week calling the decision "a sly manoeuvre, an escape route for an inquisitorial spiral fed by mere suspicions".
That, in turn, sparked a backlash from Spain's General Council of the Judiciary, the top judicial supervisory body. It warned against using language that sows doubt about judges' objectivity and independence.
Urdangarin is accused along with a former business partner of creaming off six million euros ($8 million) in public funds from contracts awarded to Noos, a charitable foundation.
Cristina sat on the board of Noos and Urdangarin was its chairman.
Investigators suspect that a separate company jointly owned by the couple, Aizoon, served as a front for laundering embezzled money.
Questioned in court by Castro in February, Cristina said she had simply trusted her husband and had no knowledge of his business affairs.
A mother of four with a master's degree from New York University, Cristina was once considered untouchable as a member of the royal family.
But the so-called Noos affair fanned public anger against the monarchy and the ruling class during the recent years of economic hardship in Spain.
The scandal soured the reign of Felipe's father Juan Carlos, who gave up the throne this month after 39 years so his son could freshen up the image of the monarchy.
Urdangarin and Cristina have been excluded from royal activities since 2011.