Brazil's federal prosecutor has challenged the constitutionality of the so-called World Cup law which was signed last year by Brazil President Dilma Rousseff.

The law gives FIFA, the world governing body of football, guarantees it says it needs to organize the 2014 World Cup.

Federal prosecutor Roberto Gurgel has questioned four articles of the World Cup law. In his filing, Gurgel contends the law violates citizens' constitutional guarantee to equal treatment, as well as provisions of Brazilian tax law.

Put in place last year, the legislation was delayed several times in heated debates in Brazil's Congress, where critics argued the national government was giving FIFA too much power.

Saint-Clair Milesi, a spokesman for the local organizing committee, said there would be ''no comment on an on-going process.''

The prosecutor's office confirmed the challenge on Wednesday. The action was filed on June 17, two days after the start of the Confederations Cup - the tune-up event for the World Cup.

According to the filing, the World Cup law violates the constitution by requiring the state to assume civil responsibility - instead of FIFA - for any damages during the events.

''The exception given to FIFA, its subsidiaries, legal representatives, consultants and its employees manifestly violate'' the taxpayers' equal status under Brazilian law. ... ''Legislators cannot favor a taxpayer in detriment to another, but may only identify situations in which there are differences which justify different treatment.''

The two-week Confederations Cup was targeted by protesters, angry about Brazil's poor public services, education and hospitals, and upset the country is spending about $14 billion to organize the World Cup. The bill is expected to be even larger for the 2016 Rio de Janeiro Olympics.

About $3.3 billion of that money will go toward new stadiums - or to remodel older ones. About 90 percent of the financing is public, although when Brazil won the bid, it said no public money would be needed to finance stadium construction.

At the height of the protests, one million people took to the streets. Protests at the six venues for the Confederations Cup were met by volleys of tear gas, shock grenades and rubber bullets.

The Confederations Cup final, won 3-0 by Brazil over Spain, was played at Rio's Maracana stadium on June 30. A security force estimated at 11,000 used tear gas outside the venue as the match was going on, with tear gas detected by fans inside the 79,000-seat venue.

The prosecutor's office said the case would be heard by Brazil's federal supreme court, though a timetable was not immediately made public.