Complex sentence: The next day, Rousseff appointed Lula as her chief of staff in what "was widely seen as an attempt to protect him from the investigation because ministers and lawmakers can only be tried by Brazil's Supreme Court".
Split into simpler sentences: The next day, Rousseff appointed Lula as her chief of staff. This "was widely seen as an attempt to protect him from the investigation because ministers and lawmakers can only be tried by Brazil's Supreme Court".