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Additional Laboratory Requests

The Los Angeles County Department of Medical Examiner performs analyses in Drug Chemistry (medical evidence collected from the death scene), Toolmark Analysis in biological specimens, Toxicology, and Trace Evidence (Gunshot Residue analysis). Other common requests of the laboratory are detailed below. To learn more about the main functions of the laboratory, see below.

For current fees and/or specific requests not detailed here, please contact the Forensic Science Laboratory at (323) 343-0530.

Lab Email

Forensic Science Laboratory

TOXICOLOGY

The toxicology section performs analyses on postmortem and human performance (antemortem) specimens (blood, urine, etc.). Requests for testing that go beyond the investigative purposes of the Department or other law enforcement entities depend on next of kin authorization, medical examiner approval and/or the laboratory's availability of methodology and specimens. For tests that require referral to outside laboratories, a fee may be required.

SPECIMEN EXTENDED HOLD or SAMPLE SPLIT REQUEST

For toxicology, the Medical Examiner retains blood specimens for no less than a year and non-blood specimens for six months. For histology, the Department retains wet tissue for four years, paraffin tissue blocks for 10 years and slides indefinitely. For a fee, anyone can request that evidence, biological, or otherwise, be held for an additional five years. The request can be made by filling out the Extend Evidence Request form. If you have any questions, you can contact the laboratory via e-mail.

After a case is finalized and closed, biological specimens can be split for independent testing. Depending on the amount available, the purpose of the split and authorization, a portion of the biological specimen(s) will be prepared for the requesting party. A fee is assessed for sample split requests.

Lab Email

Extend Evidence Request

TRACE EVIDENCE GUNSHOT RESIDUE ANALYSIS

The SEM Lab has two Scanning Electron Microscopes with Energy Dispersive X-ray Spectrometers that utilize automated GSR search software and follows up with manual confirmation of any GSR particles. All results are technically and administratively reviewed prior to release and a general report of the findings is provided for each case analysis. Law enforcement and legal entities can submit GSR Samples to the SEM Lab by any carrier with a reputable tracking system and signature confirmation. The samples for every submitted case should be accompanied by the following downloadable GSR Case Processing Form. The Laboratory analysts can also provide, for an hourly fee, expert testimony for any GSR analysis performed. Please contact the SEM lab via e-mail for more information.

SEM Lab Email

Gun Shot Residue Case Processing

PATERNITY or BIOLOGICAL SAMPLE needed for DNA Purposes

The Medical Examiner collects a biological sample on all decedents. Although the Laboratory does NOT perform paternity or DNA testing, it can provide a sample to a DNA testing laboratory of the family's choice. A list of possible DNA testing laboratories is available below. Please provide the following and e-mail the laboratory to facilitate this:

Next of kin authorization;
Contact information for the DNA laboratory of your choice; and
Check or money order for the Specimen Handling fee.

Lab Email

List of Labs

Next of Kin Authorization Form

Glossary of Terms

Autopsy

also known as a post-mortem examination, necropsy (particularly as to non-human bodies), autopsia cadaverum, or obduction — is a highly specialized surgical procedure that consists of a thorough examination of a corpse to determine the cause and manner of death and to evaluate any disease or injury that may be present. It is usually performed by a specialized medical doctor called a pathologist.

Biological specimens

blood, sections of organs, vitreous, bile, and urine.

Cause of death

an injury or disease that ultimately leads to death of the individual, generally determined by medical examiners or coroners.

Certificate of Religious Belief

in California, in order to execute a certificate of religious belief, a person must be 18 years of age or older and must state in clear and unambiguous language that any postmortem anatomical dissection or that specified procedures would violate the religious convictions of the person. The certificate must be signed and dated by the person in the presence of at least two witnesses. Each witness must also sign the certificate and must print on the certificate his or her name and residence address. California law allows the state to override religious objection if the coroner "has a reasonable suspicion that the death was caused by the criminal act of another or by a contagious disease constituting a public health hazard."

Chain of custody

a method of keeping track of who has handled a piece of evidence and when.

County Disposition

The County of Los Angeles will cremate the remains of a decedent and hold the cremains (ashes) for a period of time (about 3 years) before the ashes are interred in a common gravesite at the LA County Cemetery.

Decomposition

the disintegration of body tissues after death.

DME

Department of Medical Examiner

Evidence

any physical items such as bullets, hairs, fibers, biological fluids, etc., documents and statements that are included in a legal investigation for the jury’s or judge’s consideration in the determination of an individual’s guilt or innocence.

Forensic pathologist

A medical doctor who specializes in the sub-specialty of pathology that focuses on determining the cause of death by examining a corpse. The autopsy is performed by the pathologist usually during the investigation of criminal law cases and civil law cases in some jurisdictions.

Forensic Science

Forensic Science is the application of all forms of science to aid legal investigations.

Indigency

The lack of ability to pay as a legal reason for having certain required fees waived; being declared eligible for free services.

Manner of death

is how the death came about. Natural - due entirely (or nearly so) to natural disease processes. Homicide - due to a volitional act of another person. Suicide - due to injury that occurred with the intent to induce self-harm or cause one’s own death. Accident - due to injury when there is no evidence of intent to harm. Undetermined - inadequate information regarding the circumstances of death to determine manner; example: individual found unconscious with massive subdural hemorrhage; in the absence of information on the events leading up to death, it is impossible to determine if the hemorrhage is due to accidental fall, homicidal violence, etc.

Medical examiner

is a medically qualified forensic pathologist and government official whose duty is to investigate deaths and injuries that occur under unusual or suspicious circumstances, to perform post-mortem examinations, and in some jurisdictions to initiate inquests.

Medicolegal Autopsy

a medicolegal autopsy is done with the possibility of litigation in mind. The autopsy is designed to determine the cause of death, properly document findings, and collect evidence. A primary objective is to try to reconstruct the circumstances and events that led to the death so that a mode (natural, accident, suicide, homicide, or undetermined) can be established. A medicolegal autopsy differs from a hospital autopsy. A hospital autopsy is designed to confirm a known or suspected disease and gain further knowledge of the disease. The emphasis is placed on the gross and microscopic examination of internal organs. In a medicolegal autopsy the emphasis is shifted to the external examination and the description of external and associated internal injuries. Microscopic examination is done only when indicated. Information about identification of the remains, time of death, evidence of drug use, age of injuries, etc., becomes important and must be recorded carefully. It is imperative that findings be recorded clearly and objectively. Any forensic pathologist should be able to interpret the findings years later without difficulty. The forensic autopsy protocol must be standardized and reproducible.

Next of Kin

aNearest relative: if married, the spouse, if no spouse then adult children, or surviving parents, or blood relative, according to California State Law, unless otherwise specified in a legal document.

Toxicology

or postmortem (after death) toxicology analyzes biological specimens collected at autopsy for the presence of drugs, toxins, and poisons to help determine cause and manner of death.