U.S. Attorney Rudolph Giuliani said yesterday that he will look into possible federal charges against Bernhard Goetz for allegedly violating the civil rights of four black teen-agers he has admitted shooting on a subway train last month.

Rev. Al Sharpton, president of the National Youth Movement, and several other black leaders have called on Giuliani to convene a federal grand jury to review the case. Sharpton claims that a Manhattan grand jury decision last week not to indict Goetz on attempted-murder charges was motivated by racism. Goetz is white.

Sharpton said he would press his case Wednesday before Justice Department officials.

Giuliani said he will meet with Sharpton and other black leaders today. He said a civil rights prosecution probably would require a showing that the shootings were racially motivated, that there was a conspiracy to violate someone's rights or that there was wrongdoing by a public official acting "under color of law."

None of these may be present in the Goetz case, said Giuliani, adding: "I don't want to create public expectation one way or the other. There are very significant legal problems."

Meanwhile, in tapes broadcast by WNBC-TV, Goetz said civilians must carry guns to defend themselves because New York's criminal justice system is a "farce" and a "self-serving bureaucracy."

"What I did, I turned into a monster . . . ," he said, adding that other people "in my shoes . . . would have done the same thing.

"People have to fight back . . . . If you don't you're just living . . . like a dog . . . . If you corner a rat and you're about to butcher it -- okay? -- the way I responded was viciously and savagely, just like a rat."

The station said the tapes were made from a telephone conversation Goetz had with a friend the day before he surrendered to police in New Hampshire.