Murderer's handwritten notes revealed by Frederick Co. prosecutors

For the first time, Frederick County prosecutors have released the writings of a murderer who investigators have said may have been plotting a mass shooting.

Joshua Eckenrode shot and killed his former high school classmate, Mason Smith, in March 2021. Both were 19 years old at the time.

Eckenrode took a plea deal last month and will spend 40 years behind bars. Prosecutors say he’ll be eligible for parole in 20 years.

Smith’s family has said they believe the murder prevented a larger tragedy for the community.

After Eckenrode was arrested, investigators found multiple guns, including two assault rifles, ammunition, explosive devices, and bomb-making material.

Joshua Eckenrode

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FOX 5 was able to view the handwritten letters and potential action plan also found in Eckenrode’s room, though both prosecutors and the sheriff’s office declined to provide copies.

In a letter to his parents, Eckenrode wrote: "To mom and dad thank you for everything you’ve given me and done for me, I’m sorry for this, none of this is on you."

The letter references unspecified things that had been bothering him, especially in the past year.

"I just can’t talk about it. Sorry, and I just want to stop, but I know that’s not gonna happen, so please don’t hate me for this. You both gave it your best, thank you, but I just can’t live in this world, I’m sorry," Eckenrode wrote.

In a letter to his sister, Eckenrode wrote: "To my sister thank you for all the good memories and times we have had together, you have always been nice to me even when I’ve been a bad person to you. I hope for the best for you and I hope life does you good. Sorry it has to come to this none of this is on you."

In a letter addressed to "my friends," Eckenrode wrote: "To my friends I hope for the best for all of you, I hope you all have good futures and live life to the fullest. I appreciate everything. Sorry for this, none of you are to blame."

READ MORE: Frederick family mourns slain teen

Eckenrode also wrote up what sheriff’s investigators called a potential action plan. It references two rifles; an AR-15 under the header "Main," and a Springfield under "Secondary." Next to each header is information about "mags on me" and numbers possibly referencing ammunition. At the bottom of the page, there’s a separate header "In Car," with additional guns listed below.

"The notes that he left behind are what they are," said Frederick County Chief Assistant State’s Attorney Mike Moore. "I wish they were more of a window into what was going on."

Moore said Eckenrode never confessed to plans for a mass shooting and never provided information on why he killed Smith.

Moore said Eckenrode and Smith met up that day for some kind of transaction involving a gun and investigators said Eckenrode later told a friend that a deal "went bad."

Investigators said the shooting happened at Eckenrode’s mother’s home and that Eckenrode put Smith’s body inside Smith’s own car. He left the vehicle on a long abandoned property on Runnymeade Drive.

"We still don’t know why Josh Eckenrode shot Mason Smith," Moore said. "We would like to, but we don’t."

Smith’s father tells FOX 5 he believes what he said following Eckenrode’s arrest last year: that his son died a hero.