Caylen Deller, 32, was sentenced to life in prison after a Florida jury convicted her of murdering her on-again, off-again boyfriend, Chad Mullen. Prosecutors said Mullen was shot at Deller’s horse farm in San Mateo in September 2024 and later buried in a shallow grave. Deller testified that she fired twice in self-defense, but jurors also convicted her of tampering with evidence and failing to report a person’s death.
| 1) | Verdict and life sentence |
| 2) | Prosecutors’ account of the killing |
| 3) | Deller’s self-defense testimony |
| 4) | Questions about the aftermath |
| 5) | Closing arguments and disputed claims |
Verdict and life sentence
The jury found Caylen Deller guilty of first-degree murder on Thursday after deliberating for more than an hour. The verdict concerned the September 2024 death of Chad Mullen, with whom Deller had an on-again, off-again relationship. The court sentenced Deller to life in prison.
Deller was also convicted of tampering with evidence and failure to report the death of a person. The case centered on events at Deller’s horse farm in San Mateo, Florida, and the discovery of Mullen’s body more than a month after he went missing.
Prosecutors’ account of the killing
Prosecutors argued that Deller killed Mullen at the farm, then enlisted a friend and used a horse to help move his body. They said the body was later placed in a shallow grave, which delayed its discovery and formed part of the state’s evidence regarding concealment.
The prosecution’s case also challenged Deller’s explanation of the shooting. Prosecutors emphasized that she did not contact law enforcement after Mullen was shot and did not notify his family. They presented evidence that Deller made 28 calls to Mullen between September 2 and September 9, 2024, despite describing him as violent.
Deller’s self-defense testimony
Deller testified on Wednesday that she shot Mullen twice because she believed he was attacking her. She said the confrontation followed her questioning of him about unproven allegations that he had sexually abused her young daughter.
According to Deller’s testimony, Mullen became angry, pinned her against a truck and grabbed her throat, making it difficult for her to breathe. She said she obtained the firearm after Mullen allegedly broke into her apartment on August 1, 2024, and that she reached for it during the confrontation.
“I pulled the trigger of the gun and shot him twice. I was extremely afraid. I shot Chad twice in self-defense.”
Deller said she did not intend to kill Mullen and believed she was protecting herself.
Questions about the aftermath
Prosecutors questioned Deller about her decision not to call 911 after the shooting. She testified that she feared police would not believe her self-defense account and that she was more concerned about getting in trouble. She gave the same explanation for not telling Mullen’s relatives.
The prosecution argued that Deller’s conduct after the shooting was inconsistent with an immediate effort to report an attack. The body’s burial in a shallow grave and the alleged assistance used to move it were also central to the additional convictions for evidence tampering and failure to report the death.
Closing arguments and disputed claims
During closing arguments Thursday, prosecutors told jurors that Deller could have contacted law enforcement to report that Mullen had attacked or charged at her. Instead, they said, she never made that report. The state used that omission, along with the handling of the body and the call records, to challenge her self-defense claim.
“She could have called law enforcement to report that Mr. Mullen attacked her or charged at her or did something to her, but she never did.”
The jury rejected Deller’s account and returned the murder conviction after its brief deliberation. The resulting life sentence closes the criminal case described in the trial record, while the additional convictions reflect the actions prosecutors attributed to her after the shooting.
| Number | Key Point |
|---|---|
| 1 | Deller was convicted of first-degree murder and sentenced to life in prison. |
| 2 | Mullen was shot at a horse farm in San Mateo in September 2024. |
| 3 | Deller claimed she fired in self-defense during an alleged attack. |
| 4 | The body was found in a shallow grave more than a month later. |
| 5 | She was also convicted of evidence tampering and failing to report the death. |
Summary
The jury determined that the shooting of Chad Mullen was murder rather than justified self-defense. Evidence about the buried body, the lack of a prompt report and Deller’s communications with Mullen supported the prosecution’s case. Caylen Deller will serve a life sentence for the first-degree murder conviction, in addition to the consequences of the related offenses.
Frequently Asked Questions
Who was convicted in the case?
Caylen Deller, 32, was convicted of murdering Chad Mullen.
What was Deller’s defense?
Deller testified that Mullen attacked her during an argument and that she shot him twice in self-defense.
What sentence did Deller receive?
She was sentenced to life in prison after being convicted of first-degree murder. She was also found guilty of tampering with evidence and failing to report a person’s death.

