THE VERDICT IS IN on Oregon's celebrated love couple. A jury of eight women and four men has decided, purely and simply, that the prosecution failed to prove beyond a reasonable doubt that John Rideout, 21, raped his wife, Greta, 23, on the afternoon of Oct. 10 in their Salem apartment.

The jury found a way to duck the larger constitutional questions of whether Oregon's new law in permitting a husband to be prosecuted for rape violates the privacy of the home, and whether it undermines the common law tradition of women as property and of the marriage contract as an unwritten stipulation of sex on demand.

The jury found reasonable doubt in a rape case most prosecutors would be sure of winning. A medical doctor who examined Greta Rideout three hours after her alleged rape testified she was "probably" forced to have intercourse. Police who were dispatched to her apartment after the incident reported she had injuries on her face. Witnesses said they heard her screaming.

"Quite frankly, I was shocked at the verdict because that particular case had more corroborating evidence of rape than most rape cases ever have," says Mary Ann Largen, of the Health, Education and Welfare Department's rape task force.

If the Rideout case proves anything, it is that spousal rape cases are going to be the hardest rape cases to prosecute. And it raises the question of whether violence in marriage, which takes the form of rape, should be prosecuted as assault -- a crime that gives jurors and prosecutors flexibility -- or whether it should be prosecuted as rape, a crime that traditionally has carried life and death penalties. A jury that can give a man six months for assaulting his wife is far more likely to find him guilty than one that is forced to give him 20 years for rape.

John and Greta Rideout agreed that they had a heated argument on Oct. 10. He testified he hit Greta after she kneed him in the groin. After that, he said, they had intercourse. It was, he said, their traditional pattern of fighting and making up.

Greta Rideout, who had left her husband twice before the incident, testified that they had fought, he hit her in the face, threatened to hit her again and she, afraid he would break her jaw, submitted.

Some fairly lurid evidence about the Rideouts' private lives emerged during the trial. She had had and affair. So had he. She taunted him, telling him she had lesbian fantasies about her neighbor and said she had had an affair with his stepbrother. The stepbrother denied this in court. And so on.

Several of the jurors have told reporters that this case was a bad one, that they could not tell who was telling the truth. The Rideouts' situation may be a little seamier than most, but jurors aren't likely to get spousal rape cases in which the couple is enjoying wedded bliss.

It's going to occur in a charged, violent marriage in which both parties have lost control of the situation. It's going to occur in a pattern of domestic violence in which both parties' credibility will be strained and questioned. It is hard to imagine a spousal rape case that can be proved unless the woman comes into court so beaten up as to be able to prove conclusively that she was raped. And then the question is which has hurt her more: Being raped by her husband or having her jaw broken?

Oregon has been in the vanguard in developing a law that permits prosecution of husbands for rape who live with their wives. New Jersey is about to follow suit. What has emerged from the Rideout trial is that Oregon has a law that doesn't really work. Sure, it's the kind of law that sounds enlightened. The case has been diverting, allowing people to make big pronouncements about women owning their own bodies. Of course they do. It's been a wonderful occasion for people to go on about how women aren't property and they are equal partners in marriage. That's all true nowadays, too, and some of the common law traditions that treat women as property, or as one with their husbands, are gradually and mercifully being eroded.

The trial was sensational and the Oregon prosecutor is not being put off by the results. He is willing to prosecute other spousal rape cases on charges of rape, and he may even win a few, and it may be that the law can withstand the constitutional tests it ultimately will face.

But what purpose is to be served by this? A woman who agrees to having her spouse prosecuted for rape agrees to bare her entire sex life. She agrees to having all the seamy aspects of her personal life and that of her spouse exposed to a jury and, in the end, she has to withstand the withering question jurors ask themselves privately: What did the woman do to bring this upon herself? Just as the woman who is raped at night on a dark street must withstand the question of what she was doing on the dark street, so must the wife who prosecutes a husband for rape withstand the test of what she did to make him do it.

No one knows how common spousal rape is. But in the past few years we have gotten a frightening idea of how common domestic violence is, in whatever form it takes. We are getting clear and unmistakable evidence that violence is a dark and common side of marriage and that women are the most common victims of spousal assault.

More and more across the country, women are beginning to go to court to defend themselves against husbands who assault them. Civil damage actions are being won against some husbands. There is, in other words, gradual progress being made in establishing that women cannot be beaten up by their spouses and their spouses cannot get off scot free.

Cases like the Rideout one do not help here. Sure, maybe some women will be encouraged to bring rape charges against their husbands, but the Rideout case, if anything, has proved that the rape cases are going to be extremely difficult to prove, and that prosecutors will fare far better by turning these into the more manageable assault cases.

No woman is helped out by a sensational trial on a sensational charge of spousal rape in which she is ruined and her husband is acquitted and the children of the marriage are branded. The woman and the prosecutor may have a shot to win, but it's a long shot and is it really worth it? Quite probably she will lose and, in losing, neither she nor the law will have done anything to curb the very real problem of violence within marriage.