KUSA – The attorneys representing the man suspected in the 2013 disappearance and presumed death of Pueblo woman Kelsie Schelling have named her own father as an alternate suspect, according to court documents obtained Thursday by 9NEWS.

Donthe Lucas pleaded not guilty to a charge of first-degree murder in the case last fall. Schelling, who was pregnant with what was believed to be Lucas’ child before her disappearance, was last seen heading from her home in Denver to Pueblo to speak to him.

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Her body has not yet been found. The case has received national media attention in the midst of pleas from her family for information and her safe return.

Lucas was arrested for a murder charge in Schelling’s death in December 2017. He was already in custody for his alleged role in a Pueblo robbery.

His defense team alleged in a court filing that Schelling’s father should also be suspected in her death due to what they say is a “history of violence” toward his daughter.

The filing cites testimony from the preliminary hearing when a Denver police detective alleged that Schelling told a friend she missed work one day because “her father would come into her bedroom – or to her room, and would, I believe she said choke her, and that she would have to sometimes punch him to get him off.”

His attorneys also say they plan to present evidence of the steps they say Schelling’s family has taken to place blame on Lucas in wake of his death.

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“The foregoing information is highly favorable to the defense, material to presenting possible theories of innocence, and its exclusion will result in irreparable prejudice to Mr. Lucas’ due process rights,” the filing says.

Lucas is scheduled to stand trial in April, and will appear in court next month for a motions hearing.

In another document, Lucas’ attorneys requested a change of venue for the trial. They allege Lucas will not be able to find an impartial jury in Pueblo because of the attention the case has received.

They also claim there’s bias based on his socioeconomic status.

“The alleged victim in this case is Kelsie Schelling, a young white woman from a prominent northeastern Colorado family,” the filing reads. “The accused is a young Afro American young male from Pueblo Colorado.”

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Lucas’ attorneys go on to say that one detective referred to him as a “hood rat from East Pueblo.”

In previous hearings, the judge has said he was not inclined to move the trial, but said he was open to hearing more arguments.

The defense team also asked that polygraph results not be admissible in court. The filing specifically cites an instance where Lucas’ team claims his mother failed a polygraph test and detectives tried to use this information to obtain a confession.