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Police on radio scanner apps: That's not a 10-4

Police Scanner is available for $2.99 in the iPhone App Store.
Police Scanner is available for $2.99 in the iPhone App Store.Juicy Development

Matthew A. Hale, 29, was arrested last week in Muncie, Ind., after he allegedly fled the scene of a failed stickup at a pharmacy. 

Police accused Hale of being the getaway driver for an accomplice who was supposed to rob the pharmacy. But Hale drove off when things went sour, only to be stopped and arrested shortly thereafter, they said. Bail was set this week at $25,000 on felony charges of attempted armed robbery.

It's all pretty run-of-the-mill stuff, except for one thing: How did Hale know the heist was falling apart inside the pharmacy as he sat outside in the car?

How did he know to take off?

Matthew Hale, it turned out, had a smartphone — specifically, a Droid from Verizon Wireless. And on that Droid he had an app that he used to monitor Muncie police radio traffic, Detective Jim Johnson said.

If you're one of the millions of smartphone users who've downloaded scanner apps with names like iScanner, PoliceStream and 5-0 Radio Police Scanner, pay attention:

You might be breaking the law. 

Hale, in fact, was initially charged with a second violation, unlawful use of a police radio, which is a misdemeanor. Court records show that prosecutors chose to go ahead only with the felony attempted robbery charges when Hale goes to court in July. 

That doesn't change things for Detective Johnson. "The statute is that if it's being used as a police radio, that's illegal to have," he told my NBC colleague Chris Profitt of WTHR-TV in Indianapolis.

50 states, 50 laws

Should you scrub that scanner app from your phone? It depends. The law, it turns out, is quite literally all over the map on whether it's legal to use scanner apps on smartphones.

"As you look across the United States, we have 50 different states, and every state has different laws on things like obstruction of justice," said Benjamin Wright, a legal scholar in data security and forensics technology at the SANS Institute in Bethesda, Md., which teaches law enforcement and other security personnel the ins and outs of technology. (An earlier version of this post misspelled Benjamin Wright's name.)

It is legal to own a police scanner radio; on that, pretty much everyone agrees. Where things get sticky is when you take it out of your home. The problem, police and legal experts say, is that if you have it with you — in other words, if it's a mobile police scanner — then you can use it the way Matthew Hale is accused of: to aid in the commission of some other crime.

At least five states — Indiana among them, along with Florida, Kentucky, Minnesota and New York — make it illegal to use a mobile police scanner without a license from the Federal Communications Commission (i.e., a ham license) or permission from local law enforcement. 

At least seven others, somewhat tautologously, make it illegal to use a mobile scanner explicitly in the commission of another crime. (They're California, Michigan, New Jersey, Oklahoma, Vermont, Virginia and West Virginia.)

In all of those states, a bewildering array of conditions and exemptions may apply: Is the radio "installed" in a vehicle or simply carried? Is it just a relay for a fixed radio? Perhaps you're a journalist on assignment — if so, you're all set in Indiana and Florida, where you're otherwise supposed to have an FCC license or the cops' permission.

'You could be at risk in any state'

The rest of the states don't clearly address the issue at all. That's because the laws were written in an era when "police scanner" meant a bulky box costing several hundred dollars that you could buy only at Radio Shack. They didn't envision a time when anyone could push a button, download an app and begin listening in immediately. 

The apps don't even turn your phone into a true scanner. Instead, they receive feeds from police, fire and EMS channels all over the country, streamed over the Internet — and over your cellular network — to your device. You don't need to be in radio range, or even in the same state, for them to work.

"The technology is Buck Rogers stuff that nobody had heard of or thought of at the time the law was written," Wright told me. "This is the latest example of old laws bumping against new technologies where the application of the law is not clear." 

"The outcome can often be a checkerboard, with very similar laws from one state to the next but different outcomes," he said. "In one state if you make it to a court, the court will rule it doesn't violate this law. Another court in another state will rule it does."

Until then, unwritten laws on obstruction of justice could apply, and that could be bad news for developers and customers alike, because "that is a general common law that doesn't have to be written down in any legislation," Wright said. Which means that "to the extent that you are using some type of app that is interpreted as obstructing justice, you could be at risk in any state, even in a state with no particular legislation."

While it's smart for app makers to include a warning in the terms of service to check your local laws, "I could envision somebody taking a hard-nosed attitude against these app makers regardless of them having these disclaimers and some prosecutor taking a position that these things are an obstruction of justice," he said. "I can envision a prosecutor trying to indict the app makers. 

"It's something for an app maker to think about. You're making 5 bucks a pop for making these apps, and you've suddenly got a criminal indictment. That is not fun to deal with."

More cases could be likely

And it means things will keep happening like what happened to Cory C. Todd of Louisville, Ky.

In November, Louisville police charged Todd with possessing a mobile radio "capable of either receiving or transmitting radio or other messages or signals used by law enforcement." 

Todd had three scanner apps installed on his phone when police searched it during their investigation of an unrelated case. He wasn't even using them at the time — he simply had them on his phone. 

(Court records don't make it clear how that charge might eventually be resolved. The question of whether police had probable cause to legally search his phone is an entirely separate, equally thorny issue.)

So far, cases like Hale's and Todd's are very rare. The apps have been on the market for only a couple of years. But it's likely that more cases are on the way, because the public likes the apps and the police don't, and the laws are squishy.

The apps may be illegal in Indiana, but "I'd rather be safe than anything else," said Eugenea Jones Bare, a homemaker and mom in Muncie. "I'd rather have my kids safe."

But Jim Johnson, the Muncie detective, was just as determined. People shouldn't have the apps, he said, because the bad guys are simply going to "use that to assist in their crimes."

More on crime and smartphones from msnbc.com:

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