The judge, Teori Zavascki, 68, died Thursday when the light aircraft in which he was flying went down off the coast of Rio de Janeiro state.
The judge, Teori Zavascki, 68, died Thursday when the light aircraft in which he was flying went down off the coast of Rio de Janeiro state, killing all five people on board.
A federal police investigation is underway. The judge's son has questioned whether the plane crash was "too much of a coincidence."
Zavascki had been studying confessions of 77 construction executives involved in the huge corruption scandal at state oil firm Petrobras.
Brazilian media have speculated that the testimony could implicate Temer. Already, much of the country's business and political elite have been snared in the corruption probe.
The judge's compilation of the confessions was to have been completed next month but will now likely be delayed.
The president attended the official funeral service in the southern city of Porto Alegre after a private wake in the morning reserved for Zavascki's close friends, family and colleagues.
Another judge involved in the Petrobras probe, Sergio Moro, attended the wake, and called his deceased colleague "a true hero."
Zavascki was buried after the service.
Temer said he would name a new judge to take Zavascki's place only after the Supreme Court decided who among the current justices would take on the unfinished probe.