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personpersonJohn SawickiJohn SawickiDigital-forensics and cell-tower expert retained by Sigfredo Garcia's defense.← All People
Expert witness

John Sawicki

Courtroom still of John Sawicki.

Digital-forensics and cell-tower expert retained by Sigfredo Garcia's defense.

AppearedGarcia–Magbanua
MentionedMagbanua Retrial
143 lines·6 proceedings·2 mentions·2 trials

About

John Sawicki was a defense digital-forensics expert whose work concerned communications records and cell-tower analysis. In the 2019 joint trial, he compared Charlie Adelson's call-detail records with iCloud data, discussed applications and tower usage associated with the records, and explained why missing cloud entries could not establish the reason for an omission or reveal a communication's content or participants. Under cross-examination, he acknowledged that phones do not always connect to the nearest tower and that an overall message count could include non-text notifications. He also identified limits created by incomplete information about Luis Rivera's phones and contacts and by communications, including FaceTime activity, that might have been deleted. In Magbanua's 2022 retrial, the defense again identified Sawicki as an expert, and the court allowed him to observe Sergeant Christopher Corbitt's testimony under reciprocal conditions.

Trial Record (6)

GMGarcia–MagbanuaSep 26, 2019 – Oct 11, 2019Called by defense

Testifying for the defense on Day 8, digital-forensics expert John Sawicki compared communications records and explained limits on inferences drawn from missing cloud data and cell-tower connections.

Day 8

DirectJohn Sawicki - DirectJohn SawickiSaam Zangeneh2highlights98lines spoken

Summary

Defense expert John Sawicki described limits in iCloud, call-detail, and cell-tower records, including messages absent from Charlie Adelson's backup.

Highlights (2)

Quote“All I can say is it's not in the icloud backup when that was created. So it could have been deleted. It could have -- there could have been some other reason it didn't back up to the cloud, but all we know is it wasn't captured.”— John SawickiQualifies the defense expert's conclusion about messages absent from the backup.Open in transcript →Watch this moment ▶
CrossJohn Sawicki - CrossJohn SawickiChristopher DeCoste2highlights10lines spoken

Summary

Sawicki explained that phones do not necessarily use the nearest cell tower and may communicate from miles away.

Highlights (2)

testimony highlightSawicki explained that a phone may connect with different towers depending on signal strength, network conditions, and geography, rather than necessarily using the nearest tower.Open in transcript →Watch this moment ▶
Quote“The cell phone is going to connect to the tower with the strongest, cleanest signal. That could be the closest tower. It could not be the closest tower.”— John SawickiSummarizes the expert's qualification that the nearest tower is not necessarily the one a phone will use.Open in transcript →Watch this moment ▶
CrossJohn Sawicki - CrossJohn SawickiAnna Norris2highlights22lines spoken

Summary

Sawicki agreed his message total could include non-text notifications and that phone activity could be consistent with Jessica Rodriguez's house.

Highlights (2)

Quote“Frankly, that's the overall number, yes.”— John SawickiSawicki clarified that the 3,084 figure was an overall count rather than a content-verified message total.Open in transcript →Watch this moment ▶
RedirectJohn Sawicki - RedirectJohn SawickiSaam Zangeneh1highlight11lines spoken

Summary

Sawicki said he lacked all of Luis Rivera's contact information and agreed that deleted FaceTime activity or disposable phones can limit phone-record comparisons.

Highlights (1)

testimony highlightSawicki testified that he had not determined how many phones belonged to Luis Rivera and did not have all of Rivera's contact information, qualifying the scope of the comparison with Charlie Adelson's records.Open in transcript →Watch this moment ▶