For decades we have looked to a web of Supreme Court decisions as the ultimate safety net to protect the innocent from wrongful conviction or detention and to shield us all from governmental abuse in the criminal process.

This safety net, fraying for years, has begun to unravel with alarming speed since the retirement last summer of Justice William Brennan Jr., the great champion of the individual in the grip of the state. Brennan’s replacement, Justice David Souter, has solidified a majority that seems in a hurry to accommodate police and prosecutors by devaluing rights.

The coalitions change, with only Chief Justice William Rehnquist voting against the criminal defendant in virtually every case. But the erosion of important rights proceeds, restrained neither by adherence to precedent nor by deference to the law-making role of the Congress.

A recent example-especially telling because the Court accepted the flimsiest of justifications for prolonging wrongful detention of innocent suspects-is the 5-4 decision in Riverside v. McLaughlin on May 13. The Court held that police could routinely jail suspects for up to 48 hours before bringing them in front of a judge to determine whether there was probable cause to arrest them.

Justice Antonin Scalia, who usually sides with Rehnquist, aptly characterized the result in his dissent: "Hereafter a law-abiding citizen wrongfully arrested may be compelled to await the grace of a Dickensian bureaucratic machine, as it churns its cycle for up to two days-never once given the opportunity to show a judge that there is absolutely no reason to hold him, that a mistake has been made."

As Scalia showed, the common-law background of the Fourth Amendment and the 1975 decision in Gerstein v. Pugh support an arrested suspect’s right to be brought before a judge as soon as one can be located and routine booking can be done- ”certainly no more than 24 hours,” except in the most extraordinary cases, and often no more than an hour or two.

But Justice Sandra Day O’Connor held for the majority, including Souter, that the state could stretch to two full days the requirement laid down in Gerstein that each suspect be brought before a judge ”promptly after arrest.”

Why so long? Her raison d’état was nothing more than administrative convenience: allowing ”an overly burdened criminal justice system” to combine the probable-cause determination with other pretrial proceedings.

Presumptively innocent arrestees must therefore wait in jail, not because the evidence against them is strong or shows that they might flee or pose a danger to others but to spare states the trouble of bringing some judges off the golf course on Sundays and the cost of hiring a few more.

For decades we have looked to a web of Supreme Court decisions as the ultimate safety net to protect the innocent from wrongful conviction or detention and to shield us all from governmental abuse in the criminal process.

This safety net, fraying for years, has begun to unravel with alarming speed since the retirement last summer of Justice William Brennan Jr., the great champion of the individual in the grip of the state. Brennan’s replacement, Justice David Souter, has solidified a majority that seems in a hurry to accommodate police and prosecutors by devaluing rights.

The coalitions change, with only Chief Justice William Rehnquist voting against the criminal defendant in virtually every case. But the erosion of important rights proceeds, restrained neither by adherence to precedent nor by deference to the law-making role of the Congress.

A recent example-especially telling because the Court accepted the flimsiest of justifications for prolonging wrongful detention of innocent suspects-is the 5-4 decision in Riverside v. McLaughlin on May 13. The Court held that police could routinely jail suspects for up to 48 hours before bringing them in front of a judge to determine whether there was probable cause to arrest them.

Justice Antonin Scalia, who usually sides with Rehnquist, aptly characterized the result in his dissent: "Hereafter a law-abiding citizen wrongfully arrested may be compelled to await the grace of a Dickensian bureaucratic machine, as it churns its cycle for up to two days-never once given the opportunity to show a judge that there is absolutely no reason to hold him, that a mistake has been made."

As Scalia showed, the common-law background of the Fourth Amendment and the 1975 decision in Gerstein v. Pugh support an arrested suspect’s right to be brought before a judge as soon as one can be located and routine booking can be done- ”certainly no more than 24 hours,” except in the most extraordinary cases, and often no more than an hour or two.

But Justice Sandra Day O’Connor held for the majority, including Souter, that the state could stretch to two full days the requirement laid down in Gerstein that each suspect be brought before a judge ”promptly after arrest.”

Why so long? Her raison d’état was nothing more than administrative convenience: allowing ”an overly burdened criminal justice system” to combine the probable-cause determination with other pretrial proceedings.

Presumptively innocent arrestees must therefore wait in jail, not because the evidence against them is strong or shows that they might flee or pose a danger to others but to spare states the trouble of bringing some judges off the golf course on Sundays and the cost of hiring a few more.

One can’t help wondering whether those in the majority know anyone who has spent two days in jail without ever seeing a judge. People from more modest circumstances will bear the brunt of the Court’s tolerance for corner-cutting by an ”overly burdened" criminal-justice system. This may help explain how the Court’s balancing of individual rights against governmental convenience produced such a skewed result.

A second, even more stark departure from precedent came in the Court’s March 26 decision in Arizona v. Fulminante, which muddied the traditionally absolute rule against using coerced confessions to obtain criminal convictions.

The Court held by 5-4, with Souter tipping the balance, that use of a coerced confession at a trial does not automatically require reversal; if the judge’s admission of the confession is found to be "harmless error," Rehnquist wrote for the Court, the conviction can stand.

He thus overruled a "vast body of precedent without a word and in so doing dislodge[d] one of the fundamental tenets of our criminal justice system," as Justice Byron White said in a dissent from the key holding.

White (who ruled for different 5-4 majorities that Oreste Fulminante’s confession had been coerced and its admission had not been harmless) is tough, unsentimental, and no more given than Scalia to coddling criminals. But he felt so strongly about the principle at stake in Fulminante that he read much of his opinion from the bench- for him, almost unheard of.

It’s true, as columnist Bruce Fein pointed out on these pages on April 15, that five justices said use of coerced confessions would seldom be deemed harmless. But it’s unrealistic to suppose the decision will not spur more coercive interrogations.

By blurring what had been a clear prohibition, the Court has sent police a message-intended or not-that coercing confessions may sometimes pay, at least if you’re not too obvious about it. The message to trial judges is that admitting an arguably involuntary confession won’t automatically blow the whole case.

In the 6-3 decision on April 16 in McCleskey v. Zant, Souter and four others also signed onto Rehnquist’s longstanding campaign to speed up the pace of executions by severely curtailing state prisoners’ access to federal habeas corpus relief.

Rehnquist had denounced the precedents allowing habeas petitioners "many bites at the apple" in a lone dissent 10 years before. He urged Congress last year to amend the statute to limit state prisoners to a single federal habeas petition except in extraordinary circumstances.

When Congress did not oblige, the Court constituted itself as a "backup legislature," in Justice Thurgood Marshall’s dissenting words, and unilaterally rewrote the law to choke off most second and successive habeas petitions that raise new challenges to a prisoner’s conviction or sentence.

Casting aside longstanding practice, Justice Anthony Kennedy’s opinion for the majority directed lower courts to dismiss such subsequent petitions as "abuse of the writ,” unless the prisoner can demonstrate that "some external impediment" prevented his lawyer from raising the new issue in his first petition.

This ruling reflected understandable frustration with multiple habeas petitions successively raising new challenges to the same conviction or sentence. But unlike some habeas reform proposals pending in Congress, the Court’s resolution did nothing to remedy the shockingly inadequate lawyering that largely explains why so many prisoners fail to raise all valid challenges in their first federal habeas petition.

Indigent prisoners, including virtually all those on death row, often get slapdash representation from court-appointed counsel at trial and in state appeals-resulting in multiple trial errors for subsequent habeas counsel to deal with-and well-intentioned but less-than-thorough representation in their first habeas petitions.

This reflects many states’ gross undercompensation of appointed trial counsel; the Court’s refusal to require appointment of any counsel at all to bring habeas petitions; the paucity of volunteer lawyers with enough time fully to investigate all possible grounds for appeal before filing first habeas petitions; and the Court’s own decisions making it almost impossible to prove ineffective assistance of counsel.

Some prisoners, apparently including Warren McCleskey, are also victimized by governmental concealment of key evidence.

The Court brushed aside strong proof that the state had initially concealed from the defense evidence that police had unconstitutionally planted in the next cell an informant who induced McCleskey to make incriminating statements about his role in a murder committed during a 1978 furniture store robbery.

The Court said prisoners who can prove their innocence will be exempted from restrictions on second habeas petitions. But this will do little to mitigate the devastating impact on death-row prisoners. Most of them are clearly guilty. But many were unfairly sentenced to death, and may, never have a full and fair shot at proving it.

These three decisions, and others in which the Court has recently extended its two-decade constriction of Fourth Amendment rights, are too technical to come across as blockbusters on the evening news. And it is still too early to write off Souter, who has not yet written a single opinion in a criminal case, as consistently pro-prosecution. But the pattern suggests an ominous shift in fundamental values at the top of our legal system, a shift that will have little impact on crime while leaving us all less free.