The bizarre but serious charge could put the fast-talk 49-year-old behind bars for five years and deliver even graver harm to Moscow's deteriorating relations with the West in President Vladimir Putin's third term.
Kasparov has been a seminal figure of the Russian opposition who has used his global fame to publish articles in the Western press detailing the difficulties human rights encountered during Putin's previous 12 years in power.
His impact on home politics has been limited almost entirely to failed efforts to merge the various forces of Russia's protest movement into a cohesive unit that could meaningfully take on Putin at the polls.
But he remains a constant presence at Moscow protests and was one of dozens detained in confrontations that broke out during Friday's sentencing to two years in prison for the three feminist protest band members.
Kasparov had defended their "punk prayer" stunt performance as "political speech that should be unconditionally protected" -- a view unanimously shared by Western powers but not the Kremlin or Russia's powerful Orthodox Church.
No charges against Kasparov have yet been filed and he only appeared Monday at a Moscow district police station to give initial testimony.
The Moscow police department said it had handed over the evidence to the federal Investigative Committee that leads almost all high-profile cases against Russian opposition members.
But the charges -- if pursued -- could deal one of the biggest blows yet to ties that are already strained from opposing views of the Syria conflict and what is believed to be Putin's decision to brook no dissent in his third term.
Kasparov dismissed the biting allegations with characteristically bitter irony on his Twitter account.
"I am sorry if the policeman who was beating me on the head had hurt his hand," the man widely regarded as history's greatest chess player tweeted.
The claims appear to revolve around evidence volunteered by a man who heads Officers of Russia -- a fringe nationalist group that on its own website sets out its mission as "providing support to the law enforcement authorities."
Officers of Russia leader Anton Tsvetkov said he had been asked by baillifs to keep an eye on who was breaking order at Friday's explosive Pussy Riot verdict reading and report any incidents to the police.
"I did not personally see the bite," Tsvetkov admitted to AFP in a telephone interview.
"But one of my assistants was told by a reporter that Kasparov had bit a policeman. She went out to investigate and eventually found the bitten policeman," he added.
"The bite was on the hand."
Tsvetkov also said he was ready to give this evidence in court if criminal proceedings are ever brought.
The story has gained broad attention in part because it has been played up by Kasparov himself.
He gave a host of interviews to both US and Russian media over the weekend citing the allegations as evidence that human rights under Putin were approaching a terminal state.
Yet there would appear to be little to gain for the Kremlin from jailing a figure of international stature with national approval ratings that have rarely been higher than a few percent.
Penalties for an assault on a police officer if convicted meanwhile range from 200,000 rubles ($6,200) to five years in jail.
Some opposition sympathisers seemed to be treating the case lightly by advising Kasparov not to submit copies of his bite marks when questioned by the police.
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