Both government agencies and private companies keep vast databases containing very sensitive and very personal information about tens or hundreds of millions of subjects. For example, the FBI’s National Crime Information Center (NCIC) keeps records on arrests, outstanding warrants, criminal histories, and other data that might be of use in investigating crime. It currently processes an average of 7.5 million transactions each day. When subjects are stopped by the police, their identities are often checked against the NCIC to see if they are currently wanted for a crime, on probation, or considered dangerous. In the private sector, large credit agencies such as TransUnion and Equifax, keep computerized credit histories on close to a hundred million people. These are searched hundreds of thousands of times each day by thousands of subscribers, whenever a customer requests credit of any kind, whether it is to apply for a loan or simply make a credit card payment.

These databases are used to make many critical decisions affecting peoples’ lives. Someone can be arrested and detained or denied a mortgage or the use of a credit card based on the data stored in them. Yet the sheer size of these databases, as well as the procedures used to collect, process and maintain the data in them, ensure that they will contain many inaccuracies. A study done by Kenneth Laudon for the Office of Technology Assessment (OTA) found that only 25.7 percent of the records sent by the FBI’s identification division were ‘complete, accurate and unambiguous.’ A higher percentage, about 46 percent, of the criminal history records in the NCIC met these standards. When Laudon checked a sample of open arrest warrants on file with the FBI against records in the local court houses where they originated, he found that over 15 percent of them were invalid, either because there was no record at all of them or they had already been cleared or vacated. Thus 15 percent of the warrants on record put their subjects at risk of being arrested for no justifiable reason.

Michael DuCross was stopped for a routine traffic violation, when a check with the NCIC showed that he was AWOL from the Marine Corps. DuCross was arrested and held for five months before it was found that he had not been AWOL at all, but had been discharged legitimately.

In 1999, Phillip Cummings, a help desk worker at a software firm, took a spreadsheet of logins and passwords when he quit, granting him access to a number of credit reports. The criminals he sold the reports to stole $50 to $100 million – no small sum for the 33,000 people whose reports were stolen.

Malcolm Byrd was sitting at home in 2003 when police officers came to his home and arrested him on a warrant for cocaine possession. Though eventually his name was cleared, Byrd learned that a criminal had used his name when he was arrested. He spent some time in jail before finally being released.

Alina got hit by a ransomware attack that encrypted and locked 5,726 files. The malware was so powerful that it was almost impossible to recover the information.

She contacted the attacker through the ransomware’s communication feature. The ransomware creators, told her she can either pay to get her files back or lose them forever. Despite backing up her files 6 months ago, she decided that losing half a year’s worth of photos, documents and other files was too much, and so decided to pay the ransom. The price to unlock her files was $500.

Andy Greenberg, once took part in a ground-breaking experiment which tested how car hacking could be done. His car would be remotely hacked while he was behind the wheel. As Andy drove on the highway, the hackers started to take control of the car. First, they activated the air vents and windshield wipers. Next, the transmission was cut and finally, they remotely activated the breaks. Even though Andy tried to control his car, the hackers had more power. The experiment uncovered a massive flaw cars which was later fixed.