Mariposa, CA….Final Update on Gerrish / Chung Family. After multiple months with the FBI computer/phone forensic team, the Mariposa County Sheriff’s Office has obtained details from Jonathan Gerrish’s phone. In October of 2021 we released the cause of death determined by the Pathologist. This was based on autopsy results, our investigation, and a multitude of toxicology/scientific test results. The cause of death for Jonathan Gerrish, Ellen Chung and Aurelia “Miju” Chung-Gerrish was determined to be Hyperthermia, and probable dehydration due to, environmental exposure. Hyperthermia- The condition of having a body temperature greatly above normal.

Using the information extracted from the phone we were able to re-create the path and timeline based on the GPS locations. The details found on the phone support the findings of a heat related incident.

Phone Results Photos: Gerrish & Chung took multiple photos throughout their hike. The following are noted on the map provided

Photo / Video 1- 7:44am – Taken just a few yards from the trail head
Photo 2- 8:00am- Trail Photo
Photo 3- 9:05am- Photo of the River
Photo 4-12 – 9:35-9:39am Photos of the river and of each other
Photo 13- 10:00am Selfie style family photo
Photo 14- 10:16am Selfie style family photo
Photo 15-16 -10:29am Creek / River photo
Photo 17- 12:25pm- Screen shot of location from Trail App

Text Message Attempt:
The following text message was attempted but not successful due to not having cellular service on the area.

11:56am- “{name redacted} can you help us. On savage lundy trail heading back to Hites cove trail. No water or ver (over) heating with baby.”

Phone call Attempts:
The following phone calls were attempted to multiple phone numbers, not including 911. There is no service in the area, therefore the calls were never connected.

Call 1- 12:09:20pm
Call 2- 12:35:48pm
Call 3- 12:36:06pm
Call 4- 12:36:19pm
Call 5- 12:36:24pm

“The cell phone data results were the last thing both the family and detectives were waiting on. The extracted information confirms our initial findings. I am very proud of my team and our partner agencies for all the work they put in. Their dedication has allowed us to close this case and answer lingering questions the family had, bringing them a little peace.”- Sheriff Jeremy Briese

Source = Mariposa Sheriff’s Office