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Dan Markel— Case Archive
personpersonJason NewlinJason NewlinLeon County State Attorney's Office investigator who testified in the Garcia–Magbanua 2019 trial, the 2022 Magbanua retrial, and the Donna Adelson 2025 trial.← All People
Law enforcementLeon County State Attorney's Office

Jason Newlin

Courtroom still of Jason Newlin.

Leon County State Attorney's Office investigator who testified in the Garcia–Magbanua 2019 trial, the 2022 Magbanua retrial, and the Donna Adelson 2025 trial.

AppearedGarcia–MagbanuaMagbanua RetrialDonna Adelson
MentionedCharlie Adelson
707 lines·33 proceedings·14 mentions·4 trials

About

Jason Newlin, an investigator with the State Attorney's Office, testified about investigative work and documentary evidence at several stages of the case. In the 2019 joint trial and Katherine Magbanua's retrial, he addressed Rivera-related interviews and proffers, the recording or nonrecording of meetings, information concerning Juan Marcos Vega, and a river search that recovered a firearm later found not to match the case evidence. He acknowledged problems with his initial approach to Vega but rejected claims that investigators coached Rivera or shaped his statements for a plea agreement. In Charlie Adelson's trial, his recorded role was limited to being exempted from the sequestration order. In Donna Adelson's trial, he testified about State's Exhibit 60, which paired divorce filings with emails and planner material; he described evidence that allegations later used in the "Grandma Motion" had previously been forwarded to Donna Adelson while acknowledging uncertainty about her receipt of the filed motion and the authorship of some communications.

Trial Record (33)

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

Called by the defense on Day 8, State Attorney's Office investigator Jason Newlin testified about a river search that recovered a gun not matched to the case projectiles and about the scope and documentation of investigative interviews.

Day 1

Day 4

Day 8

DirectJason Newlin - DirectJason NewlinChristopher DeCoste4highlights138lines spoken

Summary

Jason Newlin described a gun search based on limited information, acknowledged an improper approach to questioning Juan Marcos Vega, and faced defense questions about unrecorded interviews.

Highlights (4)

evidence eventNewlin described searching river crossings after information relayed from Rivera's meeting, and testified that the gun recovered in the search did not relate to this case but was submitted for analysis.Open in transcript →
Quote“All I had was two bridges and a body of water, and I drove as far as I could make it that day. I went all the way to the Suwannee River which has two bridges and a body of water, but it was too big of an area to go by myself. So I went back, and then another day went with two other people.”— Jason NewlinNewlin described the limited information that prompted the initial firearm search.Open in transcript →
Quote“I wasn't just going to throw it away or put it -- you know, hide it under a different case. So the best decision was put it under this case because that's what we were looking for.”— Jason NewlinNewlin explained why he submitted a recovered gun for analysis despite believing it was unrelated to the case.Open in transcript →
rulingThe court sustained the State's hearsay objection and limited questioning about information concerning Juan Marcos Vega to whether Newlin interviewed him, not the substance of statements or prosecutorial decision-making.Open in transcript →

Day 9

Day 10

KMMagbanua RetrialMay 18, 2022 – May 27, 2022Called by defense

Called by the defense as an adverse witness on Day 7, State Attorney's Office investigator Jason Newlin addressed Rivera-related interviews, recording practices, and investigative follow-up. He later denied that investigators coached Rivera or required particular statements for his plea agreement.

Day 4

Day 5

Day 7

DirectJason Newlin - DirectJason NewlinChristopher DeCoste2highlights154lines spoken

Summary

Defense questioned investigator Jason Newlin about Rivera's discovery, proffers, and the limited recordings of meetings preceding Rivera's statement naming Katie.

Highlights (2)

Quote“It's the opportunity for an individual to tell the truth. And anything they say that incriminates themselves can't be used against them at that point in time.”— Jason NewlinNewlin described his understanding of the purpose and protection of a proffer.Open in transcript →Watch this moment ▶
DirectJason Newlin - Direct (Continued)Jason NewlinChristopher DeCoste2highlights120lines spoken

Summary

Defense questioned investigator Jason Newlin about follow-up on a recovered gun, social-media records, and information concerning Juan Marcos Vega that it argued could bear on Luis Rivera's account.

Highlights (2)

testimony highlightNewlin described recovering and testing a gun found under an Aucilla River bridge after information from Rivera's attorneys, while acknowledging it was a different make and model from the murder weapon.Open in transcript →Watch this moment ▶
Quote“And they were telling us that the gun should have been dumped within an hour after the homicide somewhere on I-10, near two bridges, a body of water and before I-75. So that's where I went looking.”— Jason NewlinNewlin clarified that the location information came through Rivera's attorneys and described how it led to the Aucilla River search.Open in transcript →Watch this moment ▶
RedirectJason Newlin - RedirectJason NewlinChristopher DeCoste2highlights22lines spoken

Summary

Newlin described the September 2019 jail meeting with Magbanua, said he did not know whether she had a protection agreement, and said nobody laughed during it.

Highlights (2)

Quote“You kept throwing hints that you had a piece of evidence that we'd missed and overlooked. And we knew what that piece was and it -- there was no surprise to it. And so, yeah, it didn't go anywhere.”— Jason NewlinNewlin described investigators' view of the defense's attempt to raise additional evidence during the meeting.Open in transcript →Watch this moment ▶
CACharlie AdelsonOct 26, 2023 – Nov 6, 2023

The court exempted Investigator Jason Newlin when it invoked sequestration for other prospective witnesses.

Day 1

DADonna AdelsonAug 22, 2025 – Sep 4, 2025Called by prosecution

On Day 2, State Attorney's Office investigator Jason Newlin testified about divorce filings and related communications offered through State's Exhibit 60 to address Donna Adelson's awareness of those filings.

Day 2

DirectJason Newlin - DirectJason NewlinGeorgia Cappleman1highlight26lines spoken

Summary

Newlin's proffer addressed the foundation for the 'Grandma Motion' tab and related emails in State's Exhibit 60.

Highlights (1)

evidence eventInvestigator Jason Newlin provided a foundation proffer identifying tab JJ of State's Exhibit 60 as the 'Grandma Motion,' a March 2014 filing by Dan Markel seeking to limit or restrict Donna Adelson's contact with his children.Open in transcript →Watch this moment ▶
DirectJason Newlin - DirectJason NewlinGeorgia Cappleman2highlights202lines spoken

Summary

Jason Newlin explained the documentary foundation for State's Exhibit 60, which the court admitted except for tab JJ.

Highlights (2)

evidence eventNewlin explained that State's Exhibit 60 paired each validated divorce filing with emails or planner material offered as support that it had been provided to Donna Adelson.Open in transcript →Watch this moment ▶
Quote“So each filing that we could validate would have been provided to Mrs. Adelson, is going to have a letter associated it, for example, Al. A2 would be a document validating information passed along, whether that be an email or a planner.”— Jason NewlinNewlin described how the exhibit was organized to connect individual divorce filings with claimed supporting documentation.Open in transcript →Watch this moment ▶
sidebarEmail Communication Foundation

Summary

The parties discussed whether the foundation for admitting an item tied to an email address and related communications had been established.

CrossJason Newlin - CrossJason NewlinJoshua D. Zelman2highlights10lines spoken

Summary

Newlin acknowledged uncertainty about who sent a shared-email message and recalled wendi rejecting a proposed arrangement.

Highlights (2)

Quote“I do recall an email from wendi saying, Mom, I'm not doing this.”— Jason NewlinNewlin recalled an email expressing wendi's refusal of a proposed arrangement discussed on cross-examination.Open in transcript →Watch this moment ▶
RedirectJason Newlin - RedirectJason NewlinGeorgia Cappleman1highlight2lines spoken

Summary

Newlin described Wendi and the boys' post-murder move involving Donna and Harvey Adelson.

Highlights (1)

Quote“A couple blocks away from Donna and Harvey Adelson. well, they moved in with Donna and Harvey Adelson for about a year and then permanently to a location a couple blocks away.”— Jason NewlinNewlin described the post-murder relocation arrangement involving Donna and Harvey Adelson.Open in transcript →Watch this moment ▶

Day 4

Day 6

Day 7