A white terry-cloth bathrobe was found hanging on the door leading to the master bedroom. There were traces of blood found on the outside of the robe that were so minute that they could not be typed, and blades of grass were adhering to the bottom of the garment.  Fibers from MacDonald's pajama top were also found on the inside of the robe.  CID investigators felt that MacDonald may have put the robe on prior to going outside and placing the weapons in the backyard.  Franz Grebner, William Ivory, and Robert Shaw surmised that while squatting to place the weapons on the wet ground, blades of grass stuck to the bottom of the robe.  During the April 6, 1970 interview with these same three CID investigators, MacDonald was asked whether he wore that robe at any time on February 16, 1970.  He denied wearing the robe on February 16th.  It is quite feasible that MacDonald went to the back door and underhandly tossed the Old Hickory knife and ice pick.  Considering that the distance from the back door to the large bush is only 20 feet, it is possible that MacDonald was able to toss the weapons and have them land near each other under the bush.