Kansas City, Mo. ? Attorneys for Lisa Montgomery face an immediate hurdle that could challenge the defense throughout her case: her alleged confession to killing a pregnant woman and cutting the baby from the victim’s womb.

Montgomery is due in federal court today, her first appearance before a judge in Missouri. It is just the next step in a long judicial process in which she likely will fight for a declaration of innocence — and possibly to save her own life.

The criminal complaint filed by prosecutors in the gruesome Dec. 16 death of Bobbie Jo Stinnett states that Montgomery confessed to the crime. Montgomery has not been assigned a Missouri public defender — that could come today — or hired one of her own, but what prosecutors contend is her confession will likely come into play immediately.

Montgomery, 36, of Melvern, Kan., remains detained at a federal prison in Leavenworth, Kan. Prosecutors charged her with kidnapping resulting in death in the strangling of 23-year-old Stinnett, who was eight months pregnant when she was killed. The baby Montgomery is accused of taking from Stinnett’s body survived.

Legal experts said Monday the defense might try to suppress the confession to keep a jury from hearing it. But to do so would require proving it was made improperly — without an attorney, without understanding the ramifications or after coercion.

“It’s a piece of evidence just like anything else,” said Tim Powers, a former prosecutor and judge who is now a defense attorney in Dallas. Powers said Montgomery’s defense could look for inconsistencies between the defendant’s statements to law enforcement officials and forensic evidence or otherwise seek to disprove its validity.

“There are a lot of people that admit to crimes that they did not do,” he said.

Montgomery’s case is in its infancy. Her appearance today is followed by one Thursday to determine whether she will remain behind bars.

Still to come is the convening of a grand jury and the subsequent possibility of an indictment.