MADRID — Emilio Botín, the chairman of Banco Santander and Spain’s most powerful banker, and his family will face an investigation into their tax affairs, the Spanish high court said on Thursday.

Although the case dates back to 2005, an official investigation into the tax contributions of brothers Emilio and Jaime Botín, along with their 10 children, was opened before it exceeded the period allowed by the statute of limitations, the court said.

The Botín family’s deposits at HSBC’s Swiss private banking division caught the eye of the tax authorities after a huge leak of private banking data from the unit last year. They have presented declarations to show their tax situations are normal.

“Given the impossibility of evaluating the declarations within the time period, the investigation is necessary,” the investigating judge, Fernando Andreu, said in a statement.

Judge Andreu said the total amount of potentially unpaid taxes being investigated is more than 120,000 euros, or $170,000. But he noted that if the declarations presented by the family are bona fide, the case will be dropped.

One member of the family being investigated, Ana Patricia Botín, is the head of Santander’s British banking unit.

Santander, Spain’s largest bank and the biggest in the euro zone by market capitalization, declined to comment.

HSBC said in March 2010 that a theft of data by a former employee affected up to 24,000 Swiss client accounts, dealing a heavy blow to the reputation of its private bank.

Article source: http://www.nytimes.com/2011/06/17/business/global/17santander.html?partner=rss&emc=rss