According to The Verge, Tesla records information about its customers' driving behaviour, both to improve its advanced driver assistance system, Autopilot and also in the event of a crash, to provide to investigators.
But researchers at the Netherlands Forensic Institute (NFI) discovered that Tesla's vehicles store far more detailed data than previously known, including speed, accelerator pedal position, steering wheel angle and brake usage.
Some of this data can be stored for up to a year, the institute said.
The team was investigating a crash involving a Tesla with Autopilot in use that had rear-ended another vehicle after it braked unexpectedly. Rather than seek the data from Tesla, the Dutch investigators chose to "reverse engineer" the company's data logs in order to "objectively" assess them.
"These data contain a wealth of information for forensic investigators and traffic accident analysts and can help with a criminal investigation after a fatal traffic accident or an accident with injury," Francis Hoogendijk, a digital investigator at the NFI, said in a statement.
The NFI said that even though Tesla has complied with data requests from the government in the past, the company also left out a lot of data that could have proven useful.
"Tesla however only supplies a specific subset of signals, only the ones requested, for a specific timeframe, whereas the log files contain all the recorded signals," the NFI report said.
The news of the hack could have implications for US investigators who are probing a dozen incidents of crashes involving Tesla vehicles and emergency vehicles while Autopilot is in use.