Greenville murder case hearing this morning

L-R: Dianna Siveny, Kandi Siveny, Rosie Campbell [Outagamie Co. Sheriff's Dept./Ramsey Co. (Minn.) Sheriff's Office]

APPLETON - An Outagamie County judge could decide Monday morning whether to delay a murder trial or dismiss charges against a woman accused of helping kill her domestic partner.

Prosecutors want to delay trial and may ask for the charges to be temporarily dropped in the process.

Dianna Siveny is charged with being party to first-degree intentional homicide and solicitation of substantial battery for the death of Lara Plamann. Siveny allegedly offered Rosie Campbell $5,000 to murder Plamann, but when Campbell backed out, Siveny's daughter, Kandi Siveny, allegedly shot Plamann. The murder was Oct. 17, 2007.

Campbell confessed last year to police and was expected to testify against the Sivenys. Dianna's trial is planned for Aug. 25, Kandi's is Sept. 29.

However, according to court documents filed Thursday, Outagamie County District Attorney Carrie Schneider says that Campbell is now refusing to testify, even under an offer of immunity. Calling her testimony "an important component and necessity in the prosecution of this defendant," prosecutors want to delay Dianna's trial until after Campbell's trial - which is set to start Oct. 6.

This is the latest twist in the case. Earlier this year, a judge ordered both Sivenys to be released on bond, ruling that the state violated their right to a speedy trial. Because of that, the state's petition outlines another alternative.

"The state needs to needs to proceed in a manner which requires this case to be moved until after Ms. Campbell's trial. The state understands the exceptional circumstances and request that is being made. In the alternative, if the Court will not grant this request for a new date, the State is also submitting a Motion to Dismiss the matter. The state will then act and pursue prosecution of this matter until after other mattes have been resolved," Schneider wrote.

If Campbell has not been convicted at the time of Dianna Siveny's trial, she could invoke her Fifth Amendment rights against self-incrimination. However, if Campbell has been convicted and then is called as a witness, the rules change in terms of her rights and how her testimony, or lack thereof, can be addressed by the attorneys.

A motions hearing before Outagamie County Judge Nancy Krueger is set for 9:30 a.m. Monday.

Dianna Siveny's attorney, Daniel Kaminsky, confirmed to FOX 11 he has received the motion but did not comment on it.

FOX 11's Andrew LaCombe will be at Monday's hearing and will have an update on and FOX 11 News at Five.