During day 21 of the murder trial, the Defense for Casey Anthony tried to prove she never had the body of her two-year-old daughter, Caylee in the trunk of her car.

FOX News Radio's Eben Brown, has the story from Orlando, Florida:

A highly anticipated witness was questioned by the Defense.

FOX's Phil Keating has the details from Orlando:

Early Friday morning, the crowd of people wanting a seat for the Casey Anthony murder trial got so rowdy, fist fights broke out among those desperate to get inside the courthouse.

FOX's Phil Keating explains why the crowd got out of hand:

Update:  The court has changed the way it distributes tickets for the Casey Anthony trial based on Friday's incident.  People interested in attending will now have to show up the day before at an appointed time and will be assigned a number and a time to return for their seat.  They will also have to claim it using a valid ID. 

Anthony, 25, is charged with first-degree murder in the death of Caylee and has pleaded not guilty.  The State says Caylee was suffocated by her mother with duct tape.  The Defense contends Caylee drowned in her Grandparents swimming pool.  Caylee's skeletal remains were found in December 2008.  Casey Anthony faces the death penalty if convicted.

Here is a summary of the Casey Anthony Trial: Day 21 from FOX Producer Kathleen Reuschle who was in the courtroom for the proceedings:

There was no body in the trunk. This was the bombshell opinion defense witness Dr. Timothy Huntington testified to Friday which resulted in numerous side-bars and relentless cross-examination. There was no decomposition fluid on a napkin in the trash bag in the trunk and there was no decomposition stain on the trunk liner. The insect activity that WAS detected was attracted to tobacco spittle and salami packaging in the trash bag. "I find no reason to think there ever was a body in there...the evidence doesn't make sense any way you look at it," Huntington told the Jury.

Defense Attorney Jose Baez spent the entire day with the Forensic Entomology Consultant - working to dismantle key theories in the State's case and creating doubt about evidence the Jury had seen. Huntington showed Jurors photos of a decomposed pig kept in a car trunk for 11 days, part of a study he conducted on insect activity. A large decomposition stain, and a swarm of flies were visible not just in the trunk, but also visible through the car's back window. In a decomposition event, he said, you would expect to see hundreds or thousands of flies. Contrast that with Casey's trunk which had only "the leg of one blow fly" in the trash bag. He believed the maggot pupae on the napkin in the bag was NOT feeding on decomposition fluid, as the state's witness had said, but was actually burrowing and hiding in the nooks and crannies of the napkin which is what insects in the pupae stage do- they've finished the feed stage and are fleeing. The remaining activity he stated was "unremarkable" and would be what you would normally find in the trash in the back of someone's house, feeding on small pieces of organic material ie food.

Huntington went on to say that the State in effect mischaracterized their own witnesses' findings about the substance found on the napkin in question. He felt the wording was not exact, saying Dr. Vass wrote "fatty acids LIKE adipocere" were on the napkins, that the report stopped short of actually indentifying the substance on the item. He explained even if it were the waxy decomposition substance, that usually occurs in the latter stages of decomposition. He told jurors the substance is extremely greasy and "Crisco-like" and very hard to clean-up. Baez asked him, "So you couldn't wipe it away?" To which Huntington replied, "I don't think so." (State's theory was someone wiped their hands or the trunk with the napkins to get the decomp fluid off and thru the napkins in the trash bag)

Finally, Baez showed the Jury a photo of Casey's trunk liner and asked Dr. Huntington to render an opinion on a stain, if at all visible. "It does not look like a human decomposition stain that I have seen," Huntington told the Jury.

Prosecutor Jeffrey Ashton vigorously defended his position and pointed out the pig study Huntington conducted was not relevant to Caylee Anthony's murder, because he didn't "wrap his pigs in a blanket." Caylee was a small child and her body was found wrapped in a blanket, placed in two garbage bags and then inside a laundry bag the conditions varied extensively from the witness's example. The prosecutor also challenged Huntington on the tobacco spittle and salami container theory - by breaking out the items themselves from their evidence packaging and bringing them up on the stand to examine. Ultimately Huntington had to concede there was no food in the trash bag. Ashton moved on to ask the witness if the tobacco spittle would account for the disgusting smell observed in the car. Huntington conceded it did not. While he agreed decomposition odor is very strong and tough to get out, in this case what he observed was no different than an odor he would expect to come from garbage. The prosecutor finished up by attacking Dr. Huntington's credibility indicating that he was young and only received his PhD the same year Caylee was found dead. The witness retorted that while he is the youngest board certified forensic entomologist, he has had experience with decomposition since working in a mortuary in high school.

Jurors grimaced when they had to view the photo of the decomposing pig and insects and appeared tired while waiting out several long side-bars. They laughed, as did Casey, (even though she tried to hide it) when the prosecutor asked the witness "Why didn't you wrap your pigs in a blanket?"

Editor's Note: The trial is in recess until 9AM ET Saturday morning.  On Saturday's there is only a half-day of court.