Dr Isles says that a murder victim's head injuries could not have been caused by impact against the decorations on a bed frame, because he would have to have been traveling at 120 miles per hour. Later, after she makes an instrument like a baseball bat with the same decorations as the bed frame, she says it needs to be swung like a bat at 68 mph.
Maura says the victim would have had to fallen 18 stories. A common mistake among non scientists is that bodies continue to accelerate as long as they fall. Bodies reach terminal velocity at about 1,500 feet (about 15 stories). After that the speed remains constant around 120 MPH no matter how much farther it falls.