The Supreme Court yesterday gave a new protection to criminal defendants who choose to remain silent during their trials: the right to have the jury told that silence does not imply guilt.

The court ruled, 8 to 1, that a judge, at the defendant's request, must instruct the jury not to draw an adverse inference from the invocation of the Fifth Amendment by someone on trial.

Twenty-eight states, including Maryland and Virginia, already give defendants that right, and it was required in federal trials 40 years ago by the Supreme Court. But 18 states provide no such guarantee and five prohibit the instruction entirely. Yesterday's opinion struck down Kentucky's prohibition.

Lonnie Joe Carter decined to testify at his burglary trial or at his trial on charges of being a repeat offender under Kentucky law. Following a prosecutor's repeated references to Carter's silence, Carter unsuccessfully asked the judge to say that the silence was not an "inference of guilt." The judge refused, citing the Kentucky prohibition.

Kentucky argued that the prohibition actually protects the defendant from having the silence called to the attention of the jury. But Justice Potter Stewart, writing for the majority, disagreed.

Too many view the Fifth Amendment privilege as a "'shelter for wrongdoers'," Stewart said. "A trial judge has a powerful tool at his disposal to protect the constitutional privelege -- the jury instruction -- and he has an affirmative constitutional obligation to use that tool when a defendant seeks its employment.No judge can prevent jurors from speculating about why a defendant stands mute in the face of a criminal accusation, but a judge can and must, if requested to do so, use the unique power of the jury instruction to reduce that specultion to a minimum." Justice William H. Rehnquist disented.

In other action yesterday:

The court upheld the authority of the Interstate Commerce Commission to allow railroad-line abandonments without interference from state courts. The ICC had allowed the Chicago and Northwestern railroad to abandon lines in Iowa in 1973 after the company said that repeated mudslides along the tracks made them too costly to use.

The Kalo Brick and Tile Co., which shipped bricks along the line, sued the railroad for damages. The Iowa Court of Appeals allowed the suit to proceed.

Justice Thurgood Marshall, writing for a unanimous court, ruled yesterday that Congress gave the ICC exclusive authority over abondonments.

In a ruling sought by civil rights lawyers, the justices ruled that a former flight attendant who sued Delta Airlines for racial bias does not have to pay court costs because she lost the suit.

Had the justices sided with Delta, civil rights lawyers said it would discourage people alleging discrimination from defending their rights because of the potential financial consequences if they lost in court.

Rosemary August, alleging that she was fired because she is black, sued Delta for $20,000. She rejected a $450 settlement, proceeded with her case and lost in federal court to make her pay part of its court costs.

The airline cited a federal procedural rule designed to encourage settlements by requiring payment of court costs by someone who loses a case after rejecting a settlement. But the court yesterday ruled, 6 to 3, that the rule does not apply to settlement offers made by a plaintiff, in this case Delta. Justice John Paul Stevens wrote the majority opinion. Stewart, Rehnquist and Chief Justice Warren E. Burger dissented.