"It was not enough to force the authorities to retreat. Also, the prosecutors' request that he be released ... was filed even before there was a big crowd in the streets. It's really hard to believe.
"It could be the result of some sort of intrigue -- rivalries, tensions at the very top of the Russian political elite."
But she said any political involvement would be denied by the government.
"Their response, invariably, is, it's up to the court to decide," she said. "Of course they would never admit how they interfere."
RIA Novosti reported that the trial judge "repeatedly rejected claims over his partiality and denied several motions to have him replaced."
Will the conviction affect his bid to become mayor of Moscow?
Lipman said that if Navalny's conviction was upheld by a higher court, his name would be unable to appear on an electoral ballot. However, she said he could campaign in the meantime.
"After his release yesterday he can continue running. The idea is that now he is at large up until his lawyers send in an appeal in a higher court re-examine his case. He remains at large and his verdict is not effective," she said.
She said there was "good reason to predict" that the high court would uphold the verdict before the end of the campaign for the September 8 election.
"He is still on a hook. In a theory, this higher court could make a ruling even earlier and effectively terminate his campaign."
Speaking to reporters outside court after he was released, Navalny said he would return to Moscow to discuss his next steps with his staff, RIA Novosti said.
"Regarding my participation in the elections, I am not some kind of a kitten or a puppy to whom they first say it can't participate in the elections and then they say, 'let's release him for a while so he can participate in the elections,'" he said.
Once in Moscow, he will decide whether to boycott the election or continue his campaign, he said, according to the news agency.
"We'll discuss it with the staff and with the volunteers. For now, I will stay a candidate, I am not retreating."
How has Navalny's conviction been received in Russia?
Lipman said Navalny's conviction was not likely to cost Putin any support.
"I don't think it will affect his standing in the eyes of the conservative majority. The status quo is suspicious of any troublemaker," she said.
"The minority of more modernized urban Russians -- people who resent the government for being lawless -- people likely to sympathise with Navalny -- I think they will be even angrier.
"The rift between them and the government will become even broader, but we are talking about a minority."
What about the rest of the world?
The day Navalny was convicted, the European Union's top diplomat, Catherine Ashton, called the trial a sham. And former Soviet leader Mikhail Gorbachev issued a statement saying the case "unfortunately confirms that we do not have an independent judiciary."
Rachel Denber, deputy director of Human Rights Watch's Europe and Central Asia division, said she was not surprised by the guilty verdict but was shocked by the five-year prison sentence.
"Navalny's prosecution is meant to silence a leader and messenger," she said.
Amnesty International's Europe and Central Asia program director, John Dalhuisen, said, "This was a parody of a prosecution and a parody of a trial. The case was twice closed for lack of evidence of a crime, before being reopened on the personal instruction of Russia's top investigator."
But Lipman pointed out the world had also expressed outrage over Russia's crackdown on protesters in 2011 and 2012.
"I don't think it has an effect. Not on previous occasions and not this time."