SOUTH BEND — A drastic change to a well known U.S. law could give police across America a new tool in the fight against crime. A 7-2 U.S. Supreme Court decision revises a 30-year-old ruling on what's known as "Miranda Rights."

Miranda Rights are intended to protect suspects arrested by police by barring interrogations from proceeding if the suspect asks for a lawyer. It stems from a 1966 Supreme Court ruling in Miranda v. Arizona that produced the new famous phrase that begins: "you have the right to remain silent" and ends with "you have the right to an attorney."

We've all heard it on TV before in reality cop shows or police dramas. But, just what does it really mean, and what rights does it afford to a criminal suspect?

For suspects, since 1981, it's meant that investigators can't continue questioning in a case once a person-of-interest has invoked their Miranda Right to an attorney. Without that attorney's consent, police can't legally interrogate the suspect any further.

The ruling was aimed at preventing police from coercing a person into waiving their rights to a lawyer by keeping them in custody. But, many officers said it's only led to frustrating roadblocks in important cases.

"It's been a fundamental tenant of police work that once somebody has invoked their Miranda Rights, they're unapproachable again except through their attorney. And when you go through their attorney, that's almost an automatic no," said South Bend Police Captain Phil Trent.

"After that point, it was expected that we could not approach that individual regarding the case again. So, a lot of cases just died in the water right there when we couldn't approach our suspect," Trent continued.

But, a recent case in Maryland involving a child molester who had asked for a lawyer nearly three years before he confessed challenged that ruling.

Michael Shatzer confessed in 2006 to abusing his own son. He had asked police for a lawyer when he was first questioned while already imprisoned on a child sex abuse conviction in 2003 when police questioned him about allegations he also sexually abused his own 3-year-old son.

Shatzer refused to talk and asked for a lawyer, and the questioning ended.

Then, in 2006, when Shatzer's son was old enough to offer details, a different police officer approached Shatzer in prison. He waived his Miranda rights, made incriminating statements and was eventually convicted.

But, Maryland's Court of Appeals threw out his confession, saying the passage of time did not make his first request for a lawyer less valid. The lower court judges also said that Shatzer's release from police interrogation back into the general prison population was not a sufficient break in custody to invalidate his lawyer request.

Wednesday, Justice Antonin Scalia, writing for the majority, said enough time had passed between the first and second interrogations for Shatzer, even though he was being held in prison.

"The duration of the break in custody here (2 1/2 years) was plainly enough," Scalia wrote.

"In fact, the court decided--not just two years--but two weeks was enough," Trent said. "Now, 14 days after the first approach — even if we're turned down — as long as that person's had 14 days of non-custodial, clear thinking, we can re-approach that person without their attorney."

Trent called the ruling a major surprise that could make a major impact on law enforcement across the country.

"I'm personally shocked at this," he said. "It changes a rule I've been dealing with for 23 years, and it's a major, major modification."

But, perhaps the biggest modification will come on older, "cold cases." Officers can now bring in witnesses or suspects that were previously considered untouchable to question them a second time.

"It certainly allows us the ability to keep a case open and have a little bit more hope," Trent said.

But, some are concerned the new ruling also opens the door to potential abuse of power.

"I am concerned," said South Bend criminal defense attorney Andre Gammage, a partner in the firm Berger & Gammage. "I see this as an opportunity for a person's will to be eroded if police approach, and approach, and approach every [two weeks]."

Police might have "an incentive to badger suspects through repetitive catch-and-release tactics," the National Association of Criminal Defense Lawyers told the Supreme Court.

"A police officer questioning you on day 1 or day 15, it's still an intimidating situation for you. It may be that additional information may be gained by an officer between day 1 and day 15 or sometime down the line. So, he's asking the question again and trying to do his job," Gammage said.

"But, by the same token, that person who's being questioned, I believe, just by the very nature of being questioned, feels a bit intimidated — especially when it's for the second or third time," he continued.

Gammage, and other criminal defense attorneys are worried repeated questioning could wear down a suspect's will until they do something their lawyer would advise against.

"There's a real danger in the thinking — 'if I tell them what they want to know, will they stop bothering me? They may not believe that they're incriminating themselves, and say look: if I just tell them this, or tell them something, will they leave me alone? Well, that something just might be something that would land them in jail," Gammage said.

Some lawyers have even referred to the change as a "merry-go-round" that will allow police to "legally" badger suspects. It's enough to cause Gammage to add a new piece of advice to all of his clients.

"Remember, they may now approach you again. Your answer is still: I want to talk to my lawyer. You need to invoke that again," he said.

But, Trent says, while the new law does give police more leeway, it won't result in repeated badgering.

"It certainly does give us a lot more access to a suspect. However, at some point, I think we're going to find a happy medium. Officers may determine that an individual is not going to be forthcoming with information," he said.

"Who knows," Trent continued. "In the State of Indiana or elsewhere this could still be modified and the law could be narrowed. I think after a brief period, it would be determined that the police had their answer. Beyond that would be unnecessarily badgering an individual."

Still, until that challenge comes, Trent says officers will be using the change, hoping it will help them finally close cases--both new and old--for good.

"Before it was no means no," he said. "Now, it's no means no for two weeks. After that, it might mean maybe. We'll be making a lot more phone calls and knocking on a lot more doors in the future."

The Associated Press contributed to this report.