MIAMI (CBS4) - When 31 year-old Rudy Eugene stripped naked on the McArthur Causeway a month ago, and then used his teeth to strip the face from a homeless man; many assumed Eugene was under the influence of some powerful drug.
But the Miami-Dade Medical Examiner issued a statement Wednesday saying that its toxicology lab and an outside laboratory were unable to find any cocaine, amphetamines, heroin, LSD, Oxycodone, bath salts or synthetic marijuana in Eugene's system.
In a written statement, Medical Examiner Dr. Bruce Hyma said, "Within the limits of current technology...Marijuana is the only drug identified in Mr. Rudy Eugene's body."
Some think the words "within the limits of current technology" may be key in the laboratories finding nothing but pot in Eugene's system.
H. Chip Walls, a forensic toxicologist, said makers of over-the-counter drugs like synthetic marijuana and so-called "bath salts" change the ingredients often to stay ahead of the law, and may be staying ahead of the ability of labs to detect their merchandise. As jurisdictions outlaw products, makers alter the contents.
"These drugs are being substituted on a daily basis. When one becomes controlled, they put another in that's not controlled," Walls told CBS4's Gary Nelson. "Many times the laboratories don't have the drug standards for correct identification."
Walls said some naturally grown marijuana is also being cultivated now with such high levels of the active ingredient, THC, that even pot alone has been known to set off bizarre behavior.
A Miami police officer shot and killed Eugene. The homeless man, 65 year-old Ronald Poppo, is still being treated at Jackson Memorial Hospital.
South Miami forensic psychologist, Dr. Wade Silverman, has a straightforward opinion of what caused Eugene's bizarre behavior.
"In common terms, obviously, the man was out of his mind," Silverman told CBS4 News. In short, crazy.
Silverman said there may be a clue to Eugene's psychotic break in the fact that he left his home with his bible the day of the cannibalistic attack. Some pages of the bible were torn out and strewn along the causeway, along with Eugene's clothes. There is often a religious element to schizophrenic behavior, Silverman said.
"There are all sorts of irrational justifications that the psychotic mind uses to justify their behavior," Silverman said, including the possibility that Eugene believed that God was telling him to do what he did.
Silverman cited the case of David Berkowitz, the so-called "Son of Sam" killer in New York who believed a dog had ordered him to commit a series of murders.
"Schizophrenics often believe they hear voices speaking to them, including animals, Satan, even aliens from outer space."
At the end of the day, whatever substance - or demons - possessed Rudy Eugene may remain a mystery, an enigma that followed the causeway cannibal to his grave.
for more features.