The tapes, which have not yet been ruled admissible in the double-murder trial of the American-football star, lend credibility to the defence's contention that Mr Fuhrman was a corrupt and racist police officer capable of planting evidence against Mr Simpson, who is black. They also may have profound implications for the Los Angeles Police Department as a whole.
In the transcripts from a 1985 interview given to a would-be screenwriter, Laura Hart McKinny, Mr Fuhrman describes how, after two policemen were shot in the Boyle Heights area of Los Angeles, he chased four suspects into an apartment, kicked the door down, and put a gun to the head of a girl to use her as a shield.
"There were four policemen, four guys. We broke 'em,'' he said. ''Their faces were mush.''
''They had pictures of the walls with blood all the way to the ceiling and finger marks of trying to crawl out of the room," Mr Fuhrman said in the transcripts, obtained by the Los Angeles Times.
In a police inquiry Mr Fuhrman brags that the authorities "knew damn well I did it" but he escaped any punishment. "There was nothing they could do about it. I mean, we could have murdered people."
The similarities between Mr Fuhrman's account and police records of an incident in Boyle Heights bolster the contention of Mr Simpson's lawyers that Mr Fuhrman was not making up details to impress the screenwriter, as his lawyers have suggested. A police evaluation of Mr Fuhrman in 1979 stated that he became "easily aggravated and argumentative" with a suspect and responded "with antagonism''.
Prosecutors in the Simpson case have long argued that the defence's attack on Mr Fuhrman's character and credibility does not prove he planted the bloody glove that he said he found on Mr Simpson's estate on the night Nicole Brown Simpson and Ronald Goldman were murdered. The defence challenge, the prosecution says, is intended only to distract from the question of Mr Simpson's guilt or innocence in the deaths of his ex-wife and her friend.
"Whatever his personal beliefs may be," said the deputy district attorney, Marcia Clark, on Wednesday, "the truth of the matter is that he could not have done what they're trying to prove he did."
In transcripts yet to be released, Mr Fuhrman allegedly uses the word ''nigger'' 30 times and describes 17 ways of planting and fabricating evidence. On the witness-stand Mr Fuhrman said he had struck the "n-word" from his vocabulary for the past 10 years.
Judge Lance Ito has not yet said when he will rule on the admissibility of the Fuhrman tapes, which have been edited to remove references to the judge's wife, Captain Margaret York. Capt York was Mr Fuhrman's police supervisor, and he allegedly makes detrimental comments about her on the tapes.