A D.C. Superior Court judge ruled yesterday that the wife of Paul Leon Jordan cannot be compelled to testify against Jordan during his trial on charges of murdering the 3-year-old daughter of two District police officers and the child's 56-year-old baby sitter.

Prosecutors had sought to compel the woman, Yvonne Walker, to testify at Jordan's trial, scheduled to open this week, about statements he made to her at police headquarters the night of his arrest. He allegedly told her that he had had an affair with the dead woman, had killed her and had sexually molested the child, according to lawyers at yesterday's hearing.

But Judge Eugene Hamilton ruled that Walker may assert the "marital privilege," a widely used legal principle that is part of D.C. law and states that a husband or wife may not be compelled to testify for or against a spouse.

Walker, who took the witness stand yesterday, asserted, "I don't want to hurt him. I don't believe he committed this crime . . . . I don't think he is capable."

Jordan, a chronic alcoholic who was on parole after serving recent prison terms for attempted burglary and enticing a minor child, is set to face trial for the Jan. 24 deaths of young Crystin Fletcher and her baby sitter, Cora Barnes. Their bodies were found in the child's blood-splattered bedroom of her family's home at 4321 Second St. NW.

The statements Jordan allegedly made to his wife and to investigators, including one that was videotaped, are the subject of a legal battle over whether they were obtained voluntarily and with the proper constitutional safeguards. That argument is scheduled to begin today before Hamilton.

Yesterday, however, the pretrial arguments centered on whether Walker, who married Jordan in 1972, could be forced to testify, despite the marital privilege, which both sides agreed was there to protect the sanctity of the marital relationship.

Prosecutor Amy Berman argued that there are "certain public policy exceptions" to that privilege, including a situation in which "the offense itself is so destructive to the marital relationship" that there is "nothing left to preserve." Berman also said that Walker told police on the night of Jordan's arrest that he was not her husband and that she later reiterated that before a grand jury.

Walker testified that her relationship with her husband was "off-on, off-on," because of his prison sentences and problems with alcohol. She testified she first lied about the marriage because "I was ashamed of the relationship we had," and later went to prosecutors with the truth because "my conscience bothered me."

Her attorney, Henry W. Asbill, said that Walker never believed her husband's statements about the crime, and therefore doesn't believe it has destroyed their relationship. "If the matter is cleared up," Asbill said, "she wants to make a new start with him."