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Alex Murdaugh— Case Archive
personpersonDavid GrubbsDavid GrubbsCell-phone-forensics expert who analyzed records from Paul and Maggie Murdaugh's phones.← All People
Expert witness

David Grubbs

Courtroom still of David Grubbs.

Cell-phone-forensics expert who analyzed records from Paul and Maggie Murdaugh's phones.

Appeared2023 Murder Trial
127 lines·3 proceedings·1 mention

About

David Grubbs testified for the State on Day 18 about his examination of digital records associated with Paul and Maggie Murdaugh's phones.

Grubbs testified that Paul's phone remained locked with its screen off from 8:49 until 10:18 p.m., later illuminated twice, and died at about 10:34 p.m. Rogan Gibson's final text remained unread. Grubbs could not determine what caused the later screen activations and explained that alerts, motion, tapping, handling, or other events could activate a phone's backlight.

Grubbs also explained KnowledgeC orientation records and background-process entries from Maggie's phone. He cautioned that camera, app-snapshot, and Siri artifacts did not necessarily show active use, and testified that iOS 14.6 would not record an orientation change while a phone was locked with its screen off. His testimony distinguished recorded device events from proof of a particular cause or user action.

Trial Record (3)

20232023 Murder TrialJan 23, 2023 – Mar 3, 2023Called by prosecution

David Grubbs testified as the State's cell-phone-forensics expert, analyzing records from Paul and Maggie Murdaugh's phones while explaining the limits of attributing device events to particular causes or user actions.

Day 18

Voir DireDavid Grubbs - Voir DireDavid GrubbsJohn B. Conrad1highlight9lines spoken

Summary

David Grubbs outlined his digital-forensics credentials and was qualified, without defense objection, as an expert in cell phone forensics.

Highlights (1)

Quote“I'm the chief forensic investigator for the Internet Crimes Against Children Task Force.”— David GrubbsGrubbs identified the professional position underlying the State's request to qualify him as a cell-phone-forensics expert.Open in transcript →Watch this moment ▶
DirectDavid Grubbs - DirectDavid GrubbsJohn B. Conrad4highlights118lines spoken

Summary

David Grubbs explained activity and logging limits in Paul and Maggie Murdaugh's phone records; three reports were admitted, and the court later reversed its earlier restriction on examination about Alex Murdaugh's relationship with Eddie Smith.

Highlights (4)

Quote“Yeah. He seemed to kind of fly close to the sun. The phone was always getting down to one to two percent before he would plug it in.”— David GrubbsGrubbs memorably characterized Paul Murdaugh's recurring low-battery behavior based on the reviewed data.Open in transcript →Watch this moment ▶
Quote“There's a lot -- excuse me, there's a lot of conditions that will cause a cell phone screen to come up. If you pick up your phone, that can have the phone -- the screen turn on. If you get a message or an alert from an app that you have, that can cause the screen to turn on. If the phone senses motion in a particular way, it will turn on. There's a whole variety of ways that the backlight will activate.”— David GrubbsThe explanation limits how confidently a backlight event can be attributed to human interaction.Open in transcript →Watch this moment ▶
Quote“All I can say is that the phone is interacting with the camera in some way.”— David GrubbsGrubbs declined to infer a specific user action from Maggie Murdaugh's camera-related database entry.Open in transcript →Watch this moment ▶
Quote“No, sir. That version of the IOS that she had on her phone did not log that at that particular time.”— David GrubbsGrubbs identified a system limitation that could explain the absence of an orientation record while Maggie's phone was locked and its screen was off.Open in transcript →Watch this moment ▶

Day 20