When Nascimento enters the restaurant to confront Guaracy, the man wearing the blue and white striped shirt who stands to congratulate him is Rodrigo Pimentel, the real-life former BOPE officer who co-wrote the screenplay of 'Tropa de Elite', and whom the character of Nascimento is based upon.
The character of Diogo Fraga is based on the real life Rio de Janeiro State Representative Marcelo Freixo. On the first scene with Diogo Fraga where he is giving a lecture in a classroom, the real Marcelo Freixo can be seen sitting on the first row.
Director José Padilha claimed that this movie ends his trilogy about urban violence in major Brazilian cities. The first one, Ônibus 174 (2002), was a documentary meant to explain how the state's indifference towards poor people can lead to the formation of violent criminals. The second, Elite Squad (2007), meant to explain how the state's indifference towards law enforcement agencies will often result in police brutality and corrupt officers. And finally, the last movie deals with the reasons behind the state's choice to ignore the poor and the police.
Director 'Jose Padilha' had to keep the master DVD copy (with no audio) in an undisclosed bank safe in order to avoid the same piracy issues he experienced on Elite Squad (2007). The initial idea was to document this measure with a TV news crew to promote anti-piracy initiatives but it later had to be dismissed as the branch manager was afraid of a potential heist in case its location was disclosed.