Russian opposition leader Alexei Navalny hugs his wife, Yulia, in the courtroom after being released. (Yevgeny Feldman/AFP/Getty Images)

There are two unanswered questions surrounding a Russian judge's decision Friday to release opposition leader Alexei Navalny on bail one day after he was convicted on dubious embezzlement charges and sentenced to five years in prison, sparking widespread protests. First, why would the Russian justice system, which has a record of jailing dissidents and political thorns in President Vladimir Putin's side, let him go? And, second, what does this mean for Navalny's campaign to be the next mayor of Moscow?

Both questions pertain to internal – and largely unknowable – machinations of the Russian government. But there are a few possible answers. Here are some of what presently appear to be the most plausible outcomes, with the caveat that things could change quickly --  as they already have, with Navalny's surprise release.

Why did Russian authorities let Navalny go?

(1) In response to protests: Thursday's conviction and prison sentence set off angry protests in several Russian cities, including Moscow, with more than just the usual opposition activists apparently participating. It's possible that, just as the conviction appeared politically motivated, his release also represented a political calculation to de-escalate public outrage.

(2) Gaming out the upcoming mayoral election: Russian authorities are confident, according to The Post's Will Englund, that Navalny will lose to the establishment candidate, current acting mayor Sergei Sobyanin. Allowing Navalny to run and lose could, in their thinking, lend Sobyanin's victory greater legitimacy. Most appeals take about six weeks, at which point Navalny will either be formally freed or sent back to jail, right around the time of the mayoral vote.

(3) Foreign pressure: It's possible that American and European calls for Navalny's release helped, but this seems awfully unlikely, given both that Russia rarely heeds such pressure and that the United States is right now much more occupied with NSA leaker Edward Snowden, who is still in Moscow.

(4) Or it may have just been a mistake: Some Navalny supporters are speculating, according to Englund, that the judge misunderstood his orders when he announced Navalny's release.

What happens next?

(1) Navalny loses the election and goes back to jail: This may actually be Russian authorities' goal. As the Guardian's Miriam Elder explains, "Some observers fear the surprise move was a further means of discrediting Navalny, allowing him to take part in the Moscow mayoral vote, before losing and being sent to prison as both a convicted criminal and a political failure." That's cold. But it's also consistent: Putin's government has cracked down on the opposition movement in a clear effort to discourage its middle-class supporters. Unlike in many authoritarian states, there appears to be no real government effort here to co-opt the opposition – only to suppress it.

(2) Navalny loses the election and doesn't go to jail: Whether his loss is legitimate or not, this would presumably allow Russian authorities to neutralize the immediate political threat he represents while also avoiding further public backlash.

(3) Navalny wins the election. This seems highly unlikely for obvious reasons. But if it did somehow happen, he could still theoretically lose his appeal and be sent back to prison. We're getting into deeply speculative territory here, but it's hard to imagine a Mayor Navalny in Russia's capital while Putin is still in charge; this is a guy who has called Putin's political party the "party of swindlers and thieves."

Bottom line: Don't bet against the Kremlin. As difficult as it is to know why this has happened, what Russian officials are planning and what will happen next, this is still a high-stakes political case in Putin's Russia. The end result, however we get there, is unlikely to favor Navalny at Putin's expense.