Killers only kill for one of three reasons, period. Sex, money or revenge! Track her known associates and you will find the killer. That said...this is a revenge killing. Here are my thoughts as to who and why it is in fact a revenge killing!
First, I feel that the perp is a black male, and between the ages of 18-22.
My conclusions are based upon her previous known male associates of that race and the ages are based on the fact that most kids associate with those in close proximity to their age.
Secondly, I feel that this was a single person attack and I base that upon the fact that the local sheriff has stated that there was little/no street talk about this crime. Normally in crimes, someone talks and rumors begin.
Third, I feel Jessica by prearrangement picked this person up after she left the gas station. Perhaps the person convinced her they were going to visit someone else who lived some distance away from the scene of her death, which is why she bought the extra gas (per the gas station manager/owner).
Fourth, I feel an argument ensued with the perp while driving to where her car was found or after she stopped there, but probably as she passed that particular area. The argument in the car got physical and she lost control thereby hitting her head on the dash or windshield as the car came to a stop.
Fifth, as to her cell phone and the fact that the battery was removed, I think that is without merit in this particular case. I believe after her vehicle came to a stop and with the argument probably still ensuing, she attempted to place a call, perhaps to 911.
As she attempted to do so and with the argument escalating, the perp simply hit her hand to prevent her from dialing and the phone dislodged through perhaps an open window and at the same time dislodged the battery. Have you ever dropped your phone? Quite common for the battery to fall out.
Sixth, at it is dark and the assault, sexual or otherwise, continues, the perp proceeds to attempt to kill her. As the vehicle begins to burn, he has no time to try and locate the phone for fear of being caught at the location and simply flees into the darkness.
Seventh, I feel that Jessica knew the assailant and was perhaps friends with this person. It also feel this person is rather young as apparently lighter fluid in lieu of fuel was used on her body. Any adult (say over 30) would not use lighter fluid and would have simply bought gas to use as a way to light a fire.
One other observation...is it possible the perp told her to be sure and get extra gas knowing that he in fact planned to burn her and the car and wanted to be certain there was enough fuel in the tank to do the job? If he were a friend, he would know she never put much fuel in the tank. Interesting point to ponder!
To kill by burning is a very, very personal way to kill. As a career Marine I can tell you that to kill at a distance or even in a man-to-man fight i.e. a soldier in hand-to-hand combat is one thing. To kill by literally holding someone down and pouring lighter fluid into their orifices is entirely different.
Eighth, As to the airbag discussion, they would not have deployed simply by running off the road unless something was struck, and there is no evidence that anything was struck. I feel the seats were simply in a reclined/collapsed position due to the burning of the interior and the force of the fire hoses that were placed onto them.
Ninth, I think the perp was enraged and wanted to show her so to speak, or perhaps...as it is a very small community where everyone knows everyone else, and her father worked for the Sheriff's Department perhaps she had said something to a deputy about someone...either accidentally or as a snitch...and this was a way of sub-consciously sending her a message of “keep your mouth shut.”
Tenth, I do not believe that this was a KKK/white supremacists revenge attack or something of that nature as has been alluded to in previous post. Having grown up in 1960's Mississippi, that State is quite different today and like elsewhere in our nation, most races get along. Not to say 100% that it could not have happened...but I do not believe that to be the case.
Finally, I do not believe she was a Meth user or using her vehicle to cook Meth as some have surmised. I believe her death was pre-planned and not a "spur of the moment" killing. I believe the person who killed her set out with a plan to lure her to pick him up and then at some point kill her.
Sex, money or revenge? Definitely a revenge killing, but revenge of what? That's what needs to be determined!
Either way, it is a tragedy and as a retired Marine and fellow Mississippian I hope they find this disgusting animal and prepare a special gurney for him at Parchmen (the Mississippi State Prison.)
Thanks for letting me opine. This is my first post and I am happy to discuss rationally my conclusions/hypothesis.