Kansas City, Mo. ? Federal prosecutors say jurors in the upcoming trial of the Kansas woman accused of strangling an expectant mother and stealing her fetus should hear evidence that the defendant previously lied in court about a pregnancy.

Lisa Montgomery’s statement during an April 2004 child custody proceeding in Osage County, Kan., is “intrinsic” to the government’s case in the death of Bobby Jo Stinnett, prosecutors argued in a motion filed last week.

Montgomery, 39, of Melvern, Kan., is scheduled to go on trial April 30 in U.S. District Court on a charge of kidnapping resulting in death.

She is accused of driving to the northwest Missouri home of Bobbie Jo Stinnett on Dec. 16, 2004, strangling the 23-year-old woman with a rope and using a kitchen knife to cut the baby from the mother’s body. Stinnett was eight months pregnant with her first child.

The infant girl survived, and Montgomery showed her off around Melvern as her own newborn daughter before being arrested. The baby was returned to her father, Zeb Stinnett, in Skidmore, Mo.

In their motion, prosecutors said Montgomery’s false claim in April 2004 about a recent pregnancy should be admissible at her trial because it establishes a motive to kill Stinnett.

Prosecutors wrote that Montgomery had her tubes tied on Oct. 23, 1990, during surgery at Scripps Memorial Hospital in Chula Vista, Calif.

But during an April 2004 child custody hearing in Kansas, Montgomery testified falsely that she had undergone surgery in April 2002 to reverse the sterilization, prosecutors wrote. She also testified falsely that she later became pregnant but that the pregnancy ended in a stillborn delivery on May 30, 2003, prosecutors wrote.

“If the court does not find that this evidence is intrinsic to the crime committed, at a minimum it is proof of the defendant’s statements regarding being pregnant and her ability to become pregnant goes directly to establishing her motive, opportunity, intent, preparation, plan and knowledge to commit the present offense and should be admitted,” prosecutors said.