Michael Lee Smith just couldn't let it go. After snatching Patricia McDonough's bag near her Baltimore home, he started calling her with threats. In one call, McDonough was asked to stand on her porch, where she spotted a car that she believed was used by her robber. Police also saw the car in the neighbourhood, and ran its licence plate number to eventually find Smith.
But that still wasn't enough to link Smith to the crime, so police in the city on America's eastern seaboard asked the Chesapeake and Potomac Telephone Company to record numbers dialled from his home. A week after the robbery, someone from Smith's house called McDonough, giving police enough probable cause to obtain a warrant to search his home. During the search, police found a phone book that was earmarked on the page that listed McDonough's name and number. Smith was arrested, and McDonough picked him out in a line-up.
This small-time case of a Baltimore bag-snatcher, which dates back to 1976, laid the legal groundwork for today's worldwide US government surveillance of telephone records in the name of protecting Americans from terrorists.
The Supreme Court eventually heard the case of Michael Lee Smith, ruling that the government was allowed to collect his phone records to tie him to the purse-snatching. And since the September 11, 2001 terror attacks, the National Security Agency (NSA) has used that case to justify the collection of "metadata" - the duration of calls and the phone numbers used to make and receive them - of hundreds of millions of people worldwide.
But a federal judge and even the prosecutor who pressed for Smith's conviction say the government has gone too far. Now, it may well take a new Supreme Court ruling to settle whether the Baltimore case more than three decades ago can apply to global government surveillance.
"To say that a small-time robbery on the street is a precedent for what was then unforeseen and massive electronic surveillance is simply a stretch, to put it mildly," says former Maryland attorney general Stephen Sachs, who defended the government's use of phone records to arrest and convict Smith during an argument in front of the Supreme Court. The court sided with him in a 5-3 ruling in 1979.
"For present purposes, you have to say that the trapping of information from one suspect is different, for God's sake, than trapping the data of every American who uses a telephone or the internet," Sachs says. "There's a distinction of volume, of context. But that's what the Supreme Court is going to have to decide."
Throughout his trials and appeals, Smith challenged the state's seizing his telephone records without a warrant. Courts repeatedly upheld his conviction, finding that because he knowingly used the phone company to connect his calls to McDonough's home, he had effectively given information to a third party independent of the case. And once he had done that, courts ruled, he had no reasonable right to expect the records of his phone calls to remain private.
During the 1978 Supreme Court arguments, Sachs said the legal standard in Smith's case was the same as in the days when telephone operators would place calls for clients.
"In the old days, you called an operator. My argument was, you don't have the expectation of privacy because you always gave up your information when you made a call," Sachs says.
That legal standard was accepted as recently as last month, when senior US district judge Jeffrey Miller in San Diego ruled that the NSA's collection of telephone records was constitutional in a case that linked a phone number in California to one used by a suspected operative for a Somali terror group.
The NSA says it does not listen to the content of the calls, nor does it read internet messages without specific court approval on a case-by-case basis. It says it does, however, collect and store records of the time and date calls are made, how long they last, and the numbers that are used.
But on Monday, in the first ruling to take on the NSA programme, US district judge Richard Leon in Washington found that the phone records collection was likely unconstitutional and its legal foundations far outdated for current technology.
"The almost Orwellian technology that enables the government to store and analyse the phone metadata of every telephone user in the United States is unlike anything that could have been conceived of in 1979," Leon wrote. He also found that the government had not provided evidence that the surveillance programmes prevented even a single imminent terror attack.
The surveillance programmes were revealed in June by Edward Snowden, a contractor who smuggled classified documents out of the agency's computers and gave them to journalists.
In recent public hearings and speeches, US government lawyers have clung to the Smith ruling as the legal rationale showing the NSA's phone data grab was not intrusive or unconstitutional.
During a November meeting of the Privacy and Civil Liberties Oversight Board, an independent task force that is reviewing the NSA's programmes and is expected to issue a report in January, deputy assistant attorney general Brad Wiegmann said that the Baltimore case was "fundamental" to the government's argument that phone metadata is not protected by privacy rights. During that same hearing, however, senior US district judge James Carr of Toledo said the legal reasoning derived from the Baltimore case was "not a particularly reliable basis".
In the wake of Leon's ruling, legal experts and advocates for civil liberties and privacy rights are divided on whether the legal standard for surveillance will withstand the court challenges.
"The question here is, do you have the expectation of privacy for your phone records?" says Jennifer Granick, a lawyer and director of civil liberties for Stanford University's Centre for Internet and Society. "Judge Leon answered that unequivocally."
On the other hand, Brookings Institution senior fellow Benjamin Wittes questioned whether the Supreme Court is "really ready to shut down a major intelligence programme that administrations of both parties have insisted represents a crucial line of defence against terrorism".