The first day of the murder trial of Cobey Wade Lakemper was an emotional one, but day two was all about the science of a murder investigation.

The day began with a parade of investigators from the Newton County Sheriff's Office, each recalling their role in the investigation.

1st Lt. Mark Mitchell with the sheriff's office testified about being sent to Atlanta Medical Center where Wendy Cartledge-Carter, the victim in the case, was transported for surgery after being shot - allegedly by Lakemper, in the Comfort Inn where she worked - to collect the bullet that was removed from her during surgery. And a surgical technologist explained the chain of command from the time the bullet left Cartledge-Carter's body, until it was handed over to Mitchell.

Sheriff's Lt. Keith Crum explained to the jury about how an investigation works from the investigators point of view, and took them through dozens of pictures of the lobby of the hotel where the victim was shot. He also testified that he made contact with law enforcement in North Carolina after seeing that the copy of Lakemper's driver's license that was on file at the hotel had a Walnut Cove, NC address.

"When you're at a homicide there's a lot of things going on at once," Crum explained.

Crum also told jurors about searching Room 114, the one allegedly assigned to Lakemper, and finding a note on one of the bed's. The note, written in pencil on Comfort Inn stationary, said "Sorry, I already left, heard u were coming. Cobey."

He also testified that he continued to have contact with authorities in North Carolina and in January 2006 they provided him with a 9 mm semi-automatic pistol.

Former Georgia Bureau of Investigation agents William Nix and Erik Grabitt and current special agent Brian Johnston all explained how they each went about collecting evidence, preparing that evidence to go to the crime lab for testing and organizing a manhunt.

Grabitt was a crime scene specialist at the time and he collected much of the evidence found inside the room Lakemper reportedly stayed in, including the note allegedly written by Lakemper and the pencil they believed he used to write it, as well as a bar of soap with several cut hairs on it.

There was trash left in the trashcan inside the room, along with a drink bottle and towels that Lakemper may have used when he was there. Lakemper's defense attorney, Joseph Vigneri asked Grabitt if he believed a person could have taken measures to get rid of those things had they been trying to avoid identification and Grabitt conceded that they could have done so.

Johnston, with the help of North Carolina authorities, was able to obtain Lakemper's cell phone number and a description of the vehicle he was believed to be driving at the time. Using the cell phone, U.S. Marshals were able to locate Lakemper in Tennessee. Johnston explained that could be done by tracking which cell phone tower the cell phone was closest to at the time, though he was not clear on exactly what the Marshals had done specifically to capture Lakemper, who was reportedly located in a bar, drinking and playing pool. He agreed with Vigneri, when asked, that a person attempting to elude capture could have simply turned their cell phone off, which would have resulted in the inability to track it through towers.

Jurors were also told that although the crime lab in Georgia did not have the capability to test the hairs on the bar of soap, one in Connecticut was able to. It was compared to a DNA swab taken from Lakemper and came back as a match.

The longest testimony of the day belonged to GBI forensic pathologist Dr. Keith Lehman, who performed the autopsy on Cartledge-Carter following her death on Nov. 5, 2005. Cartledge-Carter had several feet of her intestine removed and had to have her colon patched because of the damage done by the 9 mm bullet. Although she had been getting better, the large wound in her abdomen (that measured roughly 13x18 inches) had to be left open because doctors kept going in to try and repair the damage.

Two days prior to her death she started spiking a fever and quickly went downhill. Lehman testified that there was a large amount of scar tissue built up in her abdomen due to the gunshot wound and subsequent surgeries. She also had the telltale signs of past infections (healing abscesses) around her intestines, as well as enlarged lymph nodes which pointed to a current infection somewhere in her body.

As the doctor explained the various complications Cartledge-Carter had because of the gunshot wound, her three grown sons cried quietly and her elderly parents held on to one another, her mother shaking her head slowly.

"The gunshot wound and then subsequent surgeries put significant stress on the body," explained Lehman. "When you have that it can exasperate any underlying natural disease and cause it to become worse... While she was somewhat ill and still debilitated, she had a sudden and downhill turn in her course at the time of her death. That type of sudden death tells us that she had a cardiac arrhythmia that led to her death which would have been triggered by the stress caused by the complications of the gunshot wound."

Although Lehman admitted that Cartledge-Carter suffered from several preexisting conditions, such as sleep apnea, diabetes, a type of lung disease which would have caused things such as asthma and morbid obesity, he was adamant that he did not believe any of those things caused her death - though all of them could have.

"She would not have died on that day had it not been for the gunshot wound," he declared.

Vigneri questioned the doctor as to the actual bacteria that was causing her infection just before her death and Lehman explained that the active infection was a type of pneumonia, a common infection for people in a hospital. Because Cartledge-Carter had an open wound on her abdomen, a tracheotomy in her neck and catheters, there were several possible entry points. Although the doctor said that one could catch the bacteria elsewhere and in a different way (such as a person with that bacteria sneezing on another person), the odds of it happening were low.

"I think it is extremely unlikely that she would have obtained that infection any other way," he testified.

Lakemper's defense attorney questioned the doctor at length about the victim's weight and the ailments she suffered from that were likely caused, at least in part, because of it. He asked several times if sleep apnea, diabetes, a slightly enlarged heart or irregular heartbeat could have caused her death, or been the underlying cause of it.

"My opinion is that she would not have died if not for the gunshot wound," said Lehman.

Friday's testimony ended with GBI firearms examiner Kyle Felix who explained that he was able to match the 9 mm gun from North Carolina with the one that was used to shoot Cartledge-Carter by comparing the bullet taken from her body with one fired from the gun at the crime lab.

The trial will resume Monday morning and witnesses from North Carolina are expected to take the stand for the prosecution.