Opposition obtained the necessary signatures for CPI to operate, but Senate President Rodrigo Pacheco opposed to establish it.
After being notified, Pacheco said that he will abide by the decision next week, but criticized its content.
Barroso reacted to a request presented to the Supreme Court by Congressmen Jorge Kajuru and Alessandro Vieira.
According to Barroso, the court understands that a CPI must be established as requirements set by the Constitution are met.
Since the beginning of the pandemic in February 2020, Bolsonaro has reduced the effects of Covid-19, which he described as a flu or cold, criticized lockdowns by state governors and questioned the use of masks.