By Estelle Shirbon

LONDON (Reuters) - British investment fund manager Bill Browder has asked a London court to throw out a libel suit brought against him by a Russian former police officer who denies allegations that he played a part in the death of the lawyer Sergei Magnitsky, court documents show.

Pavel Karpov, a former Russian Interior Ministry investigator who is on the "Magnitsky list" of people barred from the United States over the lawyer's death, is suing Browder over four videos and two articles linking Karpov to the case.

Magnitsky, who was acting for Browder and his Hermitage Capital Management at the time, was arrested after accusing Russian officials of a $230-million fraud, and died in prison in suspicious circumstances.

He was posthumously found guilty of tax evasion by a Moscow court on July 11 this year and Browder was convicted in absentia and sentenced to nine years in jail in the same trial, which was criticized by both the United States and the European Union.

Browder's campaign to vindicate Magnitsky helped to bring about the U.S. Magnitsky Act, which bars Russians suspected of involvement in the lawyer's death from the United States and freezes their assets there.

During a two-day hearing at the London High Court, which Browder attended, his lawyers argued that Karpov's libel suit against him was an abuse of process.

"An avowed purpose of (Karpov) in pursuing the claims, to attack his inclusion on the United States government's Magnitsky list, is not an appropriate use of the process of the court," the lawyers wrote in a document presented to the judge.

RUSSIAN STATE INVOLVEMENT?

They alleged that Karpov does not have the means to fund the litigation himself and that "this court cannot be satisfied that the Russian state is not behind the claims in some way".

Karpov's lawyers wrote in their own submissions that the suggestion that he was acting at the behest of the Russian state was "groundless", noting that his earlier efforts to bring claims against Browder in Russia had been unsuccessful.

"On the evidence Russian state officials ... have been hostile to (Karpov) pursuing a private remedy in Russia. This hardly fits any enthusiasm for his claim being pursued in a foreign court," they wrote.

Browder's legal team said Karpov had no connection with Britain and thus no reason to bring his suit in a British court.

They also said he could achieve no meaningful vindication through the court as it had no power to order his removal from the Magnitsky list, nor could it restrain an "international torrent of condemnation" that went beyond the videos at issue.

In the videos, available to watch on a campaigning website run by Browder, Karpov is accused of playing a part both in the alleged fraud that Magnitsky sought to expose and in the lawyer's detention and death.

Karpov denies all the allegations against him.

"The allegations complained of in this action are all grave and unqualified allegations of fact pitched at the level of guilt," his lawyers wrote.

They argued that the defendants, Browder and Hermitage Capital Management, were domiciled in Britain, which entitled Karpov to sue them in London.

The court will rule at a later date on whether to throw out the suit or allow it to proceed to a full trial.

(Editing by Kevin Liffey)