Brazil's office of the attorney general said on Friday former President Luiz Inacio Lula da Silva could exercise his role as chief of staff after a court in Rio de Janeiro struck down a second injunction blocking his Wednesday appointment, according to Reuters. Lula is likely to face more legal challenges to joining President Dilma Rousseff's government as many Brazilians believe his appointment was made to grant him immunity from money laundering charges that he denies. Only the Supreme Court can try sitting politicians in Brazil.