MIAMI (CBS4) – Sandor Guillen is charged with DUI manslaughter, but his case may spawn a second investigation into how he came to possess prescription drugs.

A CBS4 News investigation shows a Broward county physician and nurse practitioner may have violated state and federal law in the way they provided Guillen with Adderall, a psycho-stimulant containing amphetamine.

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Guillen, who was on house arrest, was jailed for four days after testing positive for the controlled drug Friday, and was unable to provide specifics of how he got it.

In a hearing Monday, Guillen’s attorney Bruce Lehr presented documents showing the drug had been prescribed by Dr. Albert F. Castellon, a Broward psychiatrist.  The judge got Castellon’s nurse practitioner Donna K. Martinez on a speaker phone during the hearing, and Martinez revealed she gave the prescription to Guillen without consulting the doctor, using a pre-signed, blank prescription pad the doctor had provided her.

“You hand out pre-printed, already signed prescriptions from the psychiatrist?” an incredulous Judge Ellen Sue Venzer asked.

“Yes, Ma’am,” Martinez replied.  “They leave me signed prescriptions.”

Broward County Sheriff’s office spokesperson Veda Coleman Wright told CBS4 News, “It is illegal for a nurse practitioner to prescribe controlled substances or for a doctor to leave pre-signed, blank prescriptions” for others.

Ashley Carr, a spokesperson for the Florida Department of Health, said state law is clear.  “Physicians may not leave blank, pre-signed prescription forms for use,” Carr said.

Dr. Castellon, the chief of psychiatry at Broward General Hospital, also has a private practice in Pompano Beach, but his nurse practitioner said he rarely is in attendance.

“How often?” asked Judge Venzer.

“He’s in the office on Wednesdays,” Martinez replied.

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In a review of his practice posted online, a patient describes Dr. Castellon as having a “caring psychiatric nurse practitioner” with “excellent medication management.”

The federal government, partly in an effort to crack down on so-called “pill mills,” strictly limits how prescriptions for controlled substances are issued.

DEA regulations say “the doctor has to sign the prescription on the day that it is given to the patient.”  That clearly did not occur in the case of Sandor Guillen.  In court Monday the judge said documents showed Dr. Castellon had not seen Guillen in more than a year.  The nurse practitioner wrote his most recent prescription for Adderall December 17th.

A DEA spokesperson would not say whether the agency is investigating the doctor and his nurse.  An agency source did tell CBS4 News that “something definitely doesn’t sound right.  There are a lot of things going on here that raise a lot of red flags.”

A spokesperson for Broward Health Systems noted that Broward General’s chief of psychiatry is “not an employee of the hospital.”

“He was elected chief by his peers, not by the hospital,” said Trish Power, Broward Health’s director of communications.  “This is not a hospital issue.”

Power hung up as a CBS4 reporter attempted to ask follow-up questions.

CBS4 News was unable to reach Dr. Castellon through Broward General, at his office in Pompano Beach, or his home in a gated, pricey community in Parkland.  Repeated telephone messages were not returned.

At the home of Nurse Practitioner Martinez, a young man who answered the door said, “no comment,” and closed the door in a reporter’s face.  Martinez also did not respond to repeated phone messages.

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Sandor Guillen, the DUI manslaughter defendant, is charged in the drunk driving death of 13 year-old Kaely Camacho near Palmetto Bay last April.