Marni Yang made two trips to a hardware store on the day she received a guide to making silencers for firearms, a police officer testified Monday, and bought many of the items called for in the book.
Yang, 43, is on trial in Lake County Circuit Court for the Oct. 4, 2007 slayings of Rhoni Reuter, 42, and Reuter's unborn daughter in Deerfield.
On Monday, Deerfield police detective Juan Mazariegos testified he discovered Yang had purchased a two-volume paperback book entitled "How To Make A Disposable Silencer" from a Pennsylvania company on Aug. 3, 2007.
Yang paid $20 extra for overnight shipping and the book was delivered to her Chicago home the next day, Mazariegos said.
Bank records found when police were secretly collecting garbage from Yang's house showed there were two charges to Yang's debit card at a Chicago Home Depot store on Aug. 4, 2007.
Mazariegos said he contacted Home Depot officials for the itemized receipts for those purchases and then went to a Waukegan branch of the store and collected the same items shown on the receipt.
The items included a cordless drill, a keyhole saw, a hacksaw, lengths of PVC and brass pipe of various diameters and a Dremel electric multipurpose tool, Mazariegos said.
All of the items were called for or suggested for use in constructing what the book called a "pipe silencer" for a firearm, Mazariegos said.
A second police officer, Jeff Ferdina of the Waukegan police department, said many of the tools Yang bought during the two trips to Home Depot were found in her home when police searched it Jan. 4, 2008.
During three days of questioning that began the day of that search, Yang admitted to police she had bought the silencer book as a "gag gift" for a friend who is a gun collector.
She is also shown on videotape explaining to the officers she bought the supplies at the Home Depot in anticipation of making a school science project for one of her children on noise dispersion.
But, she says on the videotape, she decided against attempting to build a silencer because she feared someone could be injured in demonstrating its use.
Associate Judge Christopher Stride barred the use of the tapes during Yang's trial because police disregarded her requests to see an attorney.
Yang faces up to life in prison if convicted of first-degree murder and intentional homicide of an unborn child in the case.