A former co-worker of James Emerson says he had a special curiosity in the Rhonda Mertes murder case and admitted to knowing her.
Police say the 44-year old Emerson repeatedly denied knowing Mertes when they questioned him.
The testimony came from Harold Stillman as the Emerson trial continued on Tuesday.
Emerson is accused of the 1999 murder of Mertes.
His former girlfriend's son also testified on Tuesday.
He said Emerson broke down and cried, saying he had to get out of town as the family was heading to his grandma's house to watch a news report about the Mertes murder.
The victim witness co-coordinator has asked us not to identify the young man.
Earlier Tuesday, two more Wausau police officers testified about the evidence "chain of custody."
That's the prosecution's proof the evidence was handled properly, sealed and locked up so it can't be lost, tainted or tampered with.
Police say Emerson beat the 37-year old Mertes to death to prevent her from reporting a sexual assault or attempted sexual assault.
He was arrested in 2007 when forensic tests put his DNA at the crime scene.