DURHAM, N.C. — Sixteen hours on the witness stand appeared to be taking a toll Wednesday on evidence technician Dan George during the Mike Peterson murder trial.

George again came under heavy scrutiny as defense attorney David Rudolf tried to show the state's case against Peterson is flawed.

Peterson, on trial for first-degree murder, is accused of killing his wife, Kathleen. He claims her death was an accident, occurring when she tripped and fell down a staircase in their home.

Day 16 of the trial boiled down to a battle of willpower between George and Rudolf, who questioned George for the second straight day.

George repeatedly refused to answer certain questions.

Rudolf: "Please listen to my question."

George: "Again, that's a question I can't answer."

As tension mounted in the courtroom, a frustrated Rudolf kept firing.

Rudolf: "With all due respect, sir, I am not getting any straight answers.

"Sir, I'm going to ask you the same question over and over until I get an answer. Do we understand each other?"

George: "That's correct."

Prosecutor Jim Hardin objected, saying that Rudolf was "badgering the witness."

Judge Orlando Hudson said "just ask your question, Mr. Rudolf."

Rudolf's intense cross examination focused on whether the scene and evidence were contaminated.

Rudolf: "I'm asking you, in your opinion, whether or not you think it is appropriate to take a pair of bloody shorts and put them on a window ledge?"

George: "I don't think it would have been appropriate. No, sir."

Later, Rudolph pointed out that George placed bloody clothes from Mike Peterson and his son in the same bag -- and because of that, the State Bureau of Investigation originally refused to test them.

Rudolf also showed a picture taken by police where they neglected to use a scale to show measurements.

In an attempt at damage control, the district attorney handed George a stack of other pictures, which included a scale on a step measuring the height of the step and showing blood.

Police evidence-gathering techniques will be under the microscope again Thursday. So will George, who will take the stand for the fifth straight day.