WACO, Texas (KXAN) — The lawyers for Cecily Aguilar, the woman accused of helping dispose of the body of Fort Hood soldier Vanessa Guillen, are working to have her confession in the case thrown out.

Aguilar’s attorneys argue statements she made June 30, 2020, were obtained illegally — while she was neither under arrest and hadn’t been read her Miranda rights, KPRC in Houston reports based on court documents.

Her defense is now requesting an evidentiary hearing to “resolve factual issues.”

Investigators identified two of the suspects in Guillen’s April 22 disappearance as Spc. Aaron David Robinson, 20, and Cecily Aguilar, his girlfriend. Robinson died by suicide in July 2020 after fleeing the base.

According to the criminal complaint, Robinson told Aguilar he killed Guillen by striking her in the head with a hammer on April 22. Aguilar then reportedly helped him dispose of the body, which she reportedly recognized as Guillen.

She now faces conspiracy to tamper with evidence charges. If convicted, she faces up to 20 years in federal prison. Based on court documents, Aguilar pleads “not guilty” in the case.

The hearing is currently scheduled for Saturday afternoon in Waco.