Evidence Collection Handbook - BLOOD AND OTHER BODY FLUIDS

Evidence in this category includes blood of human or animal origin, semen, saliva, urine, and skin tissue submitted for the purpose of identification and characterization according to genetic factors such as isoenzymes and DNA profiles. This evidence is called biological evidence. It does not include samples of blood or urine submitted for the determination of the presence of drugs, alcohol, or poisons. See the section on Toxicology for such evidence.

DNA typing is based on the understanding that no two persons, except identical twins, have the same DNA. Conventional serological techniques may still be employed to eliminate suspects. If the suspect cannot be eliminated by conventional techniques, the samples will then be forwarded for DNA analysis. DNA analysis gives an extremely high power of discrimination. DNA profiles from semen stains in sexual assault cases are maintained in a computer database. This database is routinely searched against itself and also a separate database containing DNA profiles from persons convicted of specific felony offenses.

Blood Evidence Value.

Blood evidence is of value in such crimes as murder, rape, assault, robbery, burglary, hit-and-run accidents, and game law violations. Blood evidence may aid an investigation by locating the crime scene, by identifying the weapon used, by proving or disproving a suspect's alibi, and by eliminating suspects. DNA profiling can be performed on any biological substance. It can also be used for the identification of bodies when samples from parents and/or children of the missing person are available.

Information Determined.

1. Analysis must be performed on a stain to determine that it is blood, since the appearance of blood varies greatly depending on the age, weather, and other factors.
2. If the sample is blood, the species origin must then be determined. Usually, it is necessary to determine if the blood is human; in certain cases, however, it must be determined from what animal non-human blood stain originated. This can be done, but, in most cases, only to the level of the taxonomic family used in animal classification.
3. If the blood is human, further classification will be achieved by isoenzyme and DNA analysis. Different individuals have different types due to the genes they received from their parents. Each type has a certain percentage of occurrence in the population. By multiplying together the frequency of occurrence of each type found, the number of people who could have been the source of that bloodstain can be determined. If one blood type is different, a person is eliminated as the possible source.
4. DNA profiling of bloodstains is now regularly performed when necessary.
5. Additional information can be obtained from the size, shape, and distribution of blood
   spatters at the scene. This information can be used to reconstruct the events that occurred during the commission of the crime. This examination sometimes needs to be performed at the crime scene. Blood spattered clothing and other items can be evaluated at the laboratory. Detailed photographs taken at the scene showing measurements of the bloodstains can greatly aid the analysis. Contact the nearest laboratory for further information.
6. The sex of the person from whom the sample originated can be determined by DNA typing.
7. Private laboratories are used to do DNA analysis in cases requiring paternity determination.
8. Generally, DNA analysis will be limited to three or four samples per case, the victim's blood, suspect's blood, and one or two questioned samples.

Other Body Fluids of Significant Value

Value.

Depending on circumstances of the case, it is sometimes helpful to identify seminal stains, saliva, or urine. DNA profiling is performed on seminal stains in order to determine if the unknown sample matches the DNA profile of the standard blood sample or not. A differential extraction technique is used on seminal stains that will separate sperm cells from the cells from the vaginal secretions allowing the generation of separate DNA profiles from the male and female portions of the stain.

There are no specific tests to identify feces; therefore, it should not be submitted for identification.

Information Determined.

1. Seminal stains. A suspected seminal stain may be identified by testing for the presence of prostatic acid phosphatase, spermatozoa or P-30 protein. Semen may be further identified by DNA typing.
2. Saliva stains. The presence of amylase is indicative of saliva. Saliva may be further identified by DNA typing.
3. Urine. The presence of creatinine and urea is indicative of urine; however, urine cannot be typed.
4. Skin tissue. It is sometimes possible to DNA type body tissues such as skin, muscle, etc.

COLLECTION OF SAMPLE AND STANDARDS

Since blood and other body fluid evidence is biological and is rapidly decomposed by bacteria and mold, it is absolutely essential that such evidence is handled properly. Please follow these instructions carefully for each type of situation in which stains of blood or other body fluids are found. IF YOU HAVE ANY QUESTIONS, PLEASE CALL THE LABORATORY. Remember safety measures for biological hazards. Always wear disposable gloves when handling material stained with blood or other body fluids. To prevent cross contamination of samples, these gloves should be changed often if they should become soiled with a biological substance. Utensils used to collect evidence should be cleaned with 10% bleach between each item collected. A mask or other protective clothing may be advisable in some cases. Please check with your agency's safety protocols for biological hazards.

Stains on Garments or Fabrics.

1. Make sure that all stains and clothing are DRY! If the stain is wet, it must be air dried away from heat and sunlight, preferably in a secure, ventilated room. The victim's items should be separated from those of the suspect during drying.
2. Package each item separately to avoid contamination and in paper to avoid further decomposition. Paper bags are recommended. DO NOT USE PLASTIC since plastic does not "breathe" and holds in moisture, permitting bacterial and fungal growth.
3. Avoid unnecessary handling of garments with blood or seminal stains.
4. Each item should be initialed and dated in an area away from the stain.

Stains on Surfaces.

1. Items to be checked for blood should not be dusted for prints. Consult with the laboratory first.
2. Whenever possible, submit the bloodstained item itself for analysis. If this is impractical, detach or cut out the part with the stain for submission. Carefully package to avoid
   contamination or loss. Do not put any tape directly on the stain.
3. Bloodstains can be swabbed off items which cannot be submitted. Swab the blood onto a cotton-tipped applicator that has been slightly dampened with distilled water, in a manner which concentrates the sample. Swab an unstained area of the same surface in the same manner for a control. Air dry and package the stain and control swabs separately in paper.
4. Concentrated stains on walls, floors, etc. (i.e., items that cannot be cut out and submitted), can be scraped off into a piece of paper which is the carefully folded (See Appendix B.) and then placed in a pillbox or other suitable container. This container and the paper should be initialed and dated or otherwise identified.
5. If the stain is moist, let it air dry first, or swab it onto a cotton tipped applicator then air dry.
6. A control sample of the reagents used during the collection process should be submitted to the laboratory. Moisten a cotton tipped applicator with the distilled water. Allow to air dry and submitted to the laboratory labeled as "Reagent Control".
7. Collect generous portions of the samples to be analyzed.

Standard samples for comparison.

If blood, semen, or saliva groupings are requested, blood samples are required from the victim, the suspect, and from anyone else who may have contributed blood, semen, saliva, or any other body secretion to the stain in question. Blood samples should be drawn in purple-capped tubes (i.e., tubes with EDTA as the preservative). The sample should then be submitted to the lab as soon as possible, along with the rest of the evidence. In the period between obtaining the blood sample and transporting it to the lab, keep it refrigerated, not frozen.

Shipment.

Deliver biological evidence to the laboratory as rapidly as possible, since certain blood group factors decompose within a few days. Check Appendix A for the closest laboratory performing serological analysis. It is best to deliver the evidence in person; however, if this is impossible, the evidence should be sent in a styrofoam cooler containing a freezer brick, not ice, by certified mail to that laboratory. Please avoid using staples since they easily puncture disposable gloves and skin and are a possible source of infection. The outer package should be marked to the attention of the Serology Section. An envelope containing the laboratory request form should be taped to the outside of the package. Liquid blood samples should not be mailed because heat may cause deterioration. Blood stained items-should also be kept away from heat. Even an hour in a car trunk in hot weather is destructive to grouping factors. The request form should have listed the names of the victim(s) and suspect(s), and their age, race, and sex. Each item submitted should be listed along with the specific examinations desired. The package should be marked with a biohazard label.

Rape Evidence

Evidence normally collected in rape or sodomy cases includes a variety of samples which are relatively constant from case to case. This hair, fiber, and biological evidence is covered in separate sections in this manual, but, because of the relatively constant type of evidence required, a separate section was considered necessary to explain rape evidence.

Value.

Evidence in rape cases is likely to link the suspect to the victim or the individuals to some location. Semen, blood, hair or foreign fibers may be transferred during a sexual assault. While the specifics of each type of evidence are discussed in the sections on serology and hairs and fibers, this section will deal with these types of evidence as they relate to rape cases. The Kentucky State Police Forensic Laboratories have sexual assault evidence collection kits available free of charge. One is for the victim (female or male) and one for the suspect. This evidence is essential for effective forensic analysis.

The Sexual Assault Evidence

Collection Kit for Female or Male Victim.

This kit for victims consists of labeled packages for properly collecting and storing evidence, a set of instructions, a Victims Medical History and Assault Information Form, and a Request for Examination form. Each item will be discussed in order so that the investigator can understand why such a sample is requested. All envelopes should be sealed with tape and properly labeled.

1. Pubic hair combings. A paper towel, a comb, and an envelope are provided to collect any loose hair and fibers from the pubic region. This sample will be used to determine if any foreign hair matching that of the suspect is present or if any fibers that might be a link to the suspect or a scene might be present.
2. Pulled pubic hairs. An envelope for at least 15 pubic hairs pulled from various pubic locations is provided. This sample is necessary for any hair comparison to give a
   determination of the range and variability of hair known to have come from the victim.
3. Pulled head hairs. An envelope for at least 15 head hairs pulled from various locations from the head is also provided. This sample is necessary for any head hair comparison to give a determination of the range and variability of head hair known to have come from the victim.
4. Blood sample. Blood should be drawn into an EDTA tube then placed on the filter paper cards provided. This is used as a standard.
5. Buccal sample. Two cheek swabs are requested. These are sometimes used as a back-up DNA standard.
6. Vaginal or Penile swabs. Four vaginal or penile swabs are requested. These are necessary to detect semen and to determine the DNA profiles present. These must be air dried and placed in the provided white envelope.
7. Control swabs. If swabs were moistened with water or saline in any step, moisten the two control swabs with the same fluid, then allow them to air dry and place in the provided white envelope.
8. Vaginal smear sample. One cardboard microscope slide mailer is provided for a vaginal smear preparation for the determination of the presence of sperm cells.
9. Other evidence swabs. There are two envelopes containing four swabs each for use for other specimens to be taken as the case indicates. There is a check off area on the envelope for marking whether the swabs are anal swabs (for cases involving anal sodomy), oral swabs (for case involving oral sodomy), external genital swabs, or dried secretion swabs. If more than one sample is required, please be sure the samples are separated from each other and properly marked as to type of sample.
10. Underpants. Collect any underwear worn by the victim after the assault.

It is not recommended that bedding be routinely submitted to the lab. Screening of bulky evidence by the investigator greatly expedites the analysis. Clothing items submitted should be individually packaged in paper bags.

The Suspect Sexual Assault Evidence
or Biological Reference Collection Kit.

This kit for suspects consists of labeled packages for evidence, instructions, and a Request for Examination form. Each item will be discussed in order so that the investigator can understand why such a sample is requested. All envelopes should be sealed with tape and properly labeled.

1. Penile swabs. This sample consists of four swabs dampened with water and then used to swab the outer surface of the penis. This sample may include vaginal secretions from the victim. These must be air dried and placed in the provided envelope.
2. Pubic hair combing. A paper towel, comb, and envelope are provided to collect any loose hair and fibers in the pubic region. This sample is used to determine if any foreign hair or fibers are resent.
3. Pulled pubic hairs. This sample consists of at least 15 pulled pubic hairs from various pubic locations. This sample is necessary for any hair comparisons.
4. Pulled head hairs. This sample consists of at least 15 pulled head hairs from various regions of the scalp. Like all pulled hair samples, it is used as a standard necessary for hair comparisons.
5. Blood sample. Blood should be drawn into an EDTA tube then placed on the filter paper cards provided. This is used as a standard.
6. Buccal sample. Two cheek swabs are requested. These are sometimes used as a back-up DNA standard.
7. Control swabs. If swabs were moistened with water or saline in any step, moisten the two control swabs with the same fluid, then allow them to air dry and place in the provided white envelope.
8. Other evidence swabs. There is an envelope containing four swabs for use for other specimens to be collected as the case indicates. There is a check off area on the envelope for listing whether the swabs are dried secretion swabs or other swabs. If more than one sample is required, please be sure to separate each type of swab from the other and to properly mark the samples.

It is sometimes appropriate for the suspect's underwear or other clothing to be submitted. Each item of clothing should be packaged separately in a paper bag.

Please note that swabs are provided in the kits. The suspect's samples, except the blood sample, can be collected by an investigator or by the suspect himself under supervision.

General Collection Information.

1. Blood standards are necessary from any individual who may have contributed to a stain in order for complete analysis to be performed.

2. Hair analysis cannot be performed without an adequate standard sample for comparison.

3. Never lick the seal of the envelopes containing biological samples. Use tape and not staples to seal packages.

4. Try to minimize the amount of the bulk evidence that is submitted. This particularly applies to bedding.

5. Be sure all envelopes and bags are properly identified as to subject, the collector of the evidence, and the date and time of collection.

6. Do not cross contaminate evidence by packaging two items in the same package.

7. Be especially thorough in relating the facts of the case to the analyst. The request form should bear the race, age, and sex of all victims and suspects.

8. Remember to use disposable gloves in handling items with stains or blood and other body fluids and use any other protective equipment as directed by your agency. All packaged evidence containing such materials should also be marked as "BIOHAZARD".

Shipment

See the Serology Section for shipping information.


 

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