A Broken iPhone
Written by Christa Miller   

The interview seemed to be going well. Christopher J. Perkins had confessed to shaking his 2-month-old son, who was in the hospital being treated for brain injuries. But before the Madison, Wisconsin detectives took him into custody, Perkins asked to send some text messages and make phone calls to speak with family and friends.

Afterward, Perkins turned over his iPhone—which had been crushed. Perkins said he had dropped it several times; due to the heavy damage sustained by the phone, however, detectives believed he had used his SUV to run it over. But Perkins, even having recanted his confession, gave his consent to search the phone.


A data-extraction unit for mobile deveices (below) was able to recover images and the contact list from this heavily damaged iPhone (above). But the digital forensics examiner from the Madison Police Department needed to make some repairs before videos, text messages, and call logs could be recovered.


After repairing the broken home button on the iPhone, the digital forensics examiner was able to obtain a full physical image of the device.

The iPhone was so badly damaged that after one attempt to retrieve its evidence, it was determined that the phone was too badly damaged to process. The prosecutor, however, refused to give up. She wanted to prove that a video Perkins had sent to the baby’s mother—that showed the injured baby in the background, with Perkins in the foreground throwing a thumbs-up and then a middle finger—came from his iPhone and was contemporaneous to the case. She also wanted the text messages he had sent before recanting.

Detective Cindy Murphy, a digital forensics examiner and a mobile forensics expert with the Madison Police Department, took the phone. Its touch screen was crushed, the home button wouldn’t work, and the extent of crush damage meant Murphy couldn’t remove the SIM card. Still, the power button was working, and an initial search with Cellebrite UFED Logical got past the backup passcode and turned up images and the contact list.

But Murphy couldn’t get at the videos, text messages, or call logs she needed that would help establish a timeline. The UFED showed an “extra info read” failure, and other forensic tools wouldn’t work because of the backup passcode. Given the iPhone’s damage, Murphy wanted to get it into device firmware update (DFU) mode and use her UFED to do a physical extraction.

This would require a working home button. The phone needed repairs, either in-house or by an authorized source. Murphy contacted a colleague for suggestions; he directed her to a website that provided both parts and step-by-step instructions.

$50 in parts later, Murphy got the home button working and was able to get a full physical image of the iPhone. “The Cellebrite UFED was the right tool for the job of getting deeper into the data,” she said. Not only did she obtain the video the prosecutor needed; she also recovered a different video that showed the baby perfectly healthy, a clue that helped narrow the case timeline.

Meanwhile, in the sms.db file, UFED Physical Analyzer provided a predictive text file and part of a deleted text message that stated, “I’m sorry for lying to y’all and involving y’all in this Ive admitted to what I done.” Perkins had sent this message to his mother.

Perkins pleaded no contest to First Degree Reckless Injury, a D Felony, because of the evidence against him. He was sentenced to eight years in prison, with another eight years of supervision afterward. “This case goes to show that sometimes taking extra time and effort is worth it,” said Murphy.

About the Author

Christa M. Miller is the Director of Product Marketing for the Mobile Forensics Division of Cellebrite. She has worked for more than ten years as a journalist, specializing in digital forensics and other high-tech topics for public safety trade magazines. Miller has a BA in Economics from Whittemore School of Business and Economics at the University of New Hampshire, and is based in South Carolina.

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