Speaking to reporters, Oliveira said he backs a "deep investigation" into the emergence of new evidence suggesting that witnesses who involved President Michel Temer in a corruption scandal might have not been forthcoming about all of their crimes.

Prosecutor General Rodrigo Janot said on Monday that billionaire meat tycoon Joesley Batista and a fellow witness seemed to have inadvertently recorded a four-hour conversation discussing crimes not covered in their plea deal bargain. They could lose immunity from prosecution and other benefits.