Maranhão's move seemed to whipsaw the entire country, including Rousseff.
In a speech today, she too seemed confused about the meaning of the decision. "I don't know the consequences," she said to a cheering crowd of supporters. "We have to find out what's happening."
Maranhão became acting Speaker of the House last week after Eduardo Cunha, the elected Speaker, was suspended by Brazil's Supreme Court. Cunha is accused of corruption by the same court.
About 70 per cent of Brazilian deputies voted last month against Rousseff, so dozens of legislators would have to change their minds about her impeachment in order for a future vote to break her in her favour.
That seems unlikely, so Maranhão's decision may only end up stalling Rousseff's impeachment, and would do little to bring stability to her Government.
"Brazil is in political intensive care, at the peak of an ethical and institutional crisis," said Claudio Lamachia, president of the Brazilian Bar Association.
"The Brazilian Bar Association is very worried about the decision taken by the interim Speaker of the House," he said.
"This sort of action appeases the momentary interests of some political groups, but ignores the legitimate decisions already taken."