Flaws In Cellphone Evidence Prompt Reviews of 10,000 Court Verdicts

Dont believe cellphone-based location data becomes important corollary to 'don't believe everything you see on the internet.' JL


Martin Sorensen reports in the New York Times:

Authorities in Denmark plan to review 10,000 court verdicts because of errors in cellphone tracking data offered as evidence. An I.T. system that converts phone companies’ data into evidence can (be) used to place a person at the scene of a crime. During conversions, the system omitted some data, creating a less-detailed image of a cellphone’s whereabouts. Some cellphone tracking data linked phones to the wrong cellphone towers, potentially connecting innocent people to crime scenes. "Lawyers will have to be aware that “evidence that may appear objective and technical doesn’t necessarily equal high evidence value.”

The authorities in Denmark say they plan to review over 10,000 court verdicts because of errors in cellphone tracking data offered as evidence.

The country’s director of public prosecutions on Monday also ordered a two-month halt in prosecutors’ use of cellphone data in criminal cases while the flaws and their potential consequences are investigated.

“It’s shaking our trust in the legal system,” Justice Minister Nick Haekkerup said in a statement.

The first error was found in an I.T. system that converts phone companies’ raw data into evidence that the police and prosecutors can use to place a person at the scene of a crime. During the conversions, the system omitted some data, creating a less-detailed image of a cellphone’s whereabouts. The error was fixed in March after the national police discovered it.

In a second problem, some cellphone tracking data linked phones to the wrong cellphone towers, potentially connecting innocent people to crime scenes, said Jan Reckendorff, the director of public prosecutions.

“It’s a very, very serious case,” Mr. Reckendorff told Denmark’s state broadcaster. “We cannot live with incorrect information sending people to prison.”

The authorities said that the problems stemmed partly from police I.T. systems and partly from the phone companies’ systems although a telecom industry representative said he could not understand how phone companies could have caused the errors.

The national police determined that the flaws applied to 10,700 court cases dating to 2012, but it is unclear whether the faulty data was a decisive factor in any verdicts. The justice minister set up a steering group to track the extent of the legal problems they may have caused and to monitor the reviews of cases that may have been affected.

Those reviews will begin with those now before the court, verdicts linked to people currently serving prison sentences and cases brought by defense lawyers, the Justice Ministry said in a letter to Parliament.

A report on each review will be forwarded to the court and the case’s defense lawyer, and cases will be retried if necessary, according to the letter.

A spokesman for the director of public prosecutions said that Denmark was informing the European authorities about the errors, but that he was not aware of any implications for trials or investigations in other countries.

The idea that the data errors might have led to incorrect prosecutions in Denmark is unsettling, said Mikael Sjoberg, the head of the Association of Danish Judges. “It puts us in a very uncomfortable situation that the foundation of our decisions is called into question,” he said.

No statistics are available on how many verdicts are reached based on cellphone tower data in the country, but the data is often used in combination with other evidence and could help tip a court’s decision in either direction, experts say.

Karoline Normann, who heads the Danish Bar and Law Society’s criminal law committee, said that while lawyers might have discussed the significance of cellphone data, they typically had not questioned its accuracy before the system errors came to light.

Now, she said, lawyers will have to be aware that “evidence that may appear objective and technical doesn’t necessarily equal high evidence value.”

Even the director of the country’s Telecom Industry Association said that while phone companies were willing to assist the police in investigations, the use of cellphone tower data in court cases went beyond its original purpose.

“We are not created to make surveillance systems, but to make phone networks,” said the director, Jakob Willer. “Our data is for our purposes so people can speak together.”

It will take some effort to re-establish the trustworthiness of such data in court, said Mr. Sjoberg of the judges’ association.

“Technology is dangerous — we all know that,” he said. “I must assume the police are focusing on their I.T. systems so this will not happen again.”

Yet regaining that trust is crucial, said Ms. Normann, the lawyer.

“Cellphone tower data has, for better or worse, been a significant part of criminal cases as they also helped document that people weren’t at a given crime scene,” she said. “Everybody’s benefited from the high evidence value, and it’s in everybody’s interest that it returns.”