SPRINGFIELD, Ohio -- Closing arguments were made late Monday afternoon and the jurors began deliberations.

Police interrogation techniques took center stage Monday in the trial of a Springfield man accused of abusing his adopted children.

A detective from the Union County Sheriff's Office spent several hours on the stand Monday being cross examined about how he interviewed James Ferguson and the children.

Police said interviews happened several years ago as authorities in Union and Clark counties investigated allegations that Ferguson and his wife were abusing their five adopted children.

Last week, the children testified that they were beaten repeatedly by James and Vonda Ferguson with belts, sticks and hammers.

The defense stressed that detectives asked the children the same questions multiple times during interviews.

The detective said the repeated questions are necessary because children are often times afraid to answer truthfully.

James Ferguson faces 30 counts of endangering children, permitting child abuse and felonious assault. His wife faces similar counts, including two charges of rape, police said.