A Limestone County judge declared a mistrial on Monday in the case of Mason Wayne Sisk, an Elkmont teen accused of having killed five of his family members in 2019. 

Sisk, now 17, has been charged with shooting and killing his father, stepmother, two brothers and his sister on Sept. 2, 2019. 

Sisk pleaded not guilty to the charges. 

Limestone County Circuit Judge Chad Wise dismissed the jury Monday morning after the discovery of additional evidence, according to multiple reports.

According to WAFF, the FBI discovered the new evidence after they were able to unlock the phone of one of Sisk’s parents on Wednesday. 

Limestone County District Attorney Brian Jones told WAFF that investigators sent Sisk’s father’s and stepmother’s phones to the FBI in 2019. Investigators could not unlock one of the phones until Wednesday, the third day of Sisk’s trial.

Last week, the prosecution presented its case against Sisk and called multiple witnesses to the stand, including family friends of the Sisks and police who were at the scene.

The prosecution unveiled a video of Sisk confessing to killing his family to former Limestone County Sheriff Mike Blakely and another investigator after being read his Miranda rights.

According to reports, Sisk called his girlfriend before he called 911. She testified Thursday and said Sisk told her he was downstairs playing video games when he heard gunshots, only to find his entire family dead. She said he was crying.

Sisk kept communicating with his girlfriend after his arrest.

Text messages from 2021 showed Sisk admitting to killing his family. He wrote that he did it because he was held at gunpoint by a man in a mask. However, in another message, he wrote he was good with a gun because he was able to shoot his family all in the head so quickly. 

Now that a mistrial has been declared, the prosecution and defense will have time to look at the new evidence. Wise ordered Sisk’s father’s phone be made available to the defense within 21 days.

The new trial date is set for Feb. 13, 2023, at 9 a.m.

To connect with the author of this story, or to comment, email will.blakely@1819news.com or find him on Twitter and Facebook.

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