Jamie Gasper walked.

His lawyer said he had not been tried in the requisite 120 days for first-degree murder, so a St. Clair County judge dismissed the charge.

It was a strange turn in a strange case: the 1994 slaying of Vincent Allen. The studious, hardworking teen ran to a bedroom window in his parents' East St. Louis house when his car alarm went off, and someone shot him through the glass.

A year passed with no arrest, before Allen's mother developed information that led to Gasper. He made a confession, but a judge threw it out after a lawyer argued it was tainted because police took it while holding his client without probable cause.

Prosecutors planned a trial anyway, but the judge calculated that the imaginary 120-day clock (which stops for defense-generated delays) had already run out.

Now, 15 years after that ruling, the rigidity of criminal law is still frustrating the families of some victims. The latest example comes from Mason County, Ill., northwest of Springfield, where relatives of a murder victim — outraged by the acquittal of the defendant — announced an online campaign to repeal protections against being tried twice for the same crime.

It will go nowhere, of course. Protection against "double jeopardy" is contained in the U.S. and Illinois constitutions, both pretty hard to amend. But the underlying complaint caught my interest, partly because it seems to run counter to the latest shift of sympathies about the American justice system.

Beginning in the 1960s, there were cries that the law was soft on criminal suspects. I think it dated to the U.S. Supreme Court's Miranda and Escobedo decisions, which led to the reading of rights that every TV crime show fan knows by heart: "You have the right to remain silent ..."

Not everybody agreed that things were soft. The O.J. Simpson murder trial in 1995 amplified a smoldering sense in the black community that the system never gave a break to suspects of color. Los Angeles braced for riots if O.J. was convicted. He wasn't. The outrage waned by 2008, when he was convicted of armed robbery and kidnapping in a bizarre case in Las Vegas. He was sentenced to 33 years and nobody rioted.

Public opinion regained some sympathy for defendants in the past decade or so, with a heightened realization across all races that innocent people — particularly those close to victims or whose lifestyle put them among "usual suspects" — sometimes do go to prison. DNA testing proved it.

An examination of capital punishment in Illinois focused national attention on mistakes. While no provably innocent people were found to have been executed, at least several were waiting in line. So the state got serious about funding a fair defense in capital cases, and eventually did away with the death penalty together.

We also have this frightening realization: Experts say three-fourths or more of the convicts cleared by DNA had been identified by witnesses. Studies show that memories can be unreliable, especially if they cross racial lines.

So if convicts are entitled to second chances, why not prosecutors, some folks in Mason County are asking.

Well, one reason is that a lot of power is already tilted the state's way. The prosecutor decides whom to charge, with what, and when. Ethically, no prosecutor should take a case to court without sufficient evidence to expect a conviction. And double jeopardy protections prevent retrials from being used as punishment.

Moreover, the prosecutor uses the public's money, while the accused must use his own — unless he's poor enough to tap the fragile resources of the public defender. Maybe we need a drive to make the state pay the legal bills of defendants who are acquitted yet financially ruined by the experience.

Through it all, justice still tends to win the day.

Remember that O.J. eventually did go to prison.

Recently, federal prosecutors filed arson-fraud charges against a woman after a double jeopardy concern prevented the state from trying her on a charge of murdering her son in a fire in Florissant.

And remember Jamie Gasper, whose clock ran out in the East St. Louis killing? An appeals court later ruled that the state actually had 11 days left to start the trial. Gasper pleaded guilty of murder in exchange for a 45-year prison term he is still serving.