He said use of the equipment, which scrambles plain text into unbreakable code, is skyrocketing among organized crime groups.

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In Mary's case, Elizabeth's master code breaker Thomas Phelippes cracked the cipher and exposed her crime.

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The methods they used to avoid detection were straight out of a crime novel - they wrote cryptic notes using numbers and letters and spoke in code on the phone.

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The code says that such surveillance would only be justified to prevent malpractice or crime.

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"We've made some pretty good progress at breaking the code of silence, " said Jeff Dion, director of the National Crime Victim Bar Association.

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To fight back, law enforcement agencies argue that everyone should store the keys to their encryption code with a third party that in turn will allow the government to access information if a crime is suspected.

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