Evidence Submission & Testing

Evidence Packaging

Evidence Swabs

• Package swabs collected from different areas into separate swab boxes.
• Label each swab box with the location collected and the case number.
• Place all swab boxes into a paper envelope and seal the envelope with evidence tape.
• Label the envelope with your initials, date, and offense number; be sure to write across both the tape and envelope.

Actual Evidence Items

• Full evidence items may be collected in lieu of swabs.
  • If fingerprints are suspected to be on the item, submit the item for fingerprint processing FIRST. After fingerprint processing, you can submit the items to the Institute’s Forensic Genetics Laboratory for DNA testing and analysis.
• Package items separately in paper bags or containers, ensuring all items are dry prior to packaging.
• Wet items must be dried prior to packaging or may be TEMPORARILY packaged in plastic for transport.
• If wet items are to be submitted to the lab in plastic, be sure to clearly indicate this on the outermost package so that the item can be dried upon arrival.
• Seal each bag or container with evidence tape.
  Label each package with your initials, date, and offense number; be sure to write across both the tape and package.

Buccal Swabs

• Collect at least two swabs from each individual, having the individual rub the swabs on the inside of his/her cheek. Place the swabs inside a swab box.
• Label each swab box with the name of the person from whom the swabs were collected, date, your initials, and the case number (or offense number).
• Package swabs from each person in a separate box.
  Place all swab boxes into a paper envelope and seal the envelope with evidence tape.
• Label the envelope with your initials, date, and case/offense number; be sure to write across both the tape and envelope.

Evidence Packaging

Drug evidence must be submitted inside an evidence container, such as a sealed evidence bag (paper or plastic), envelope or box. It is acceptable to include multiple pieces of drug evidence in one evidence container if the evidence is separated within it. When using paper bags, envelopes or boxes, each seam must be sealed with tamper-evident tape. All seals must be initialed or otherwise marked to document the person sealing the evidence. Be sure to write across both the tape and envelope.

• At a minimum, the evidence container must be labeled with the name of the submitting law enforcement agency and agency case number.
• Syringes and sharp objects must be submitted in sealed plastic puncture-resistant containers.
• All liquid evidence must be sealed in a leak-proof container.
• All plant material must be dried prior to submission to the laboratory.
• Fresh suspected khat plant material must be refrigerated. Dried suspected khat plant does not require refrigeration.
• Mushrooms must be submitted in a paper bag or envelope.

Weight Limitations

No more than 100 pounds of suspected marihuana or 20 kilograms of any other substance may be submitted per case for in-house analysis by the Institute. If the evidence weight exceeds these amounts, core sampling will be performed by Institute laboratory personnel at an off-site location designated by the submitting agency.

Purity/Quantitative Analysis

Purity testing (also known as quantitative analysis) is no longer performed on liquid preparations of codeine and hydrocodone.

Evidence Packaging

For full toxicological analysis, it is recommended that the submitting agency provide the following:

Driving While Intoxicated Cases

Drug-Facilitated Sexual Assault Cases

• Blood AND urine should be submitted for drug-facilitated sexual assault cases. Please submit two full vials of blood and at least 50 mL of urine. Blood should be collected in 10 mL glass gray-topped vials containing 100 mg sodium fluoride and 20 mg potassium oxalate. Urine may be collected in a specimen bottle or cup.
  
  Failure to submit the recommended volume of blood or urine may result in incomplete testing.

Evidence Packaging

Each specimen vial, bottle, or cup should be labeled with the following:

• Name of the individual from whom the specimen was collected
• Date and time of collection

Specimen vials, bottles, or cups should be stored inside a leak-proof container, such as a plastic bag. The samples then may be placed inside a paper specimen container, such as a cardboard box, or envelope, if desired. It is acceptable to include multiple specimen vials, bottles, or cups in one specimen container if they all pertain to the same case. The specimen container should be sealed with evidence tape and must be labeled with the following:

• Initials of the individual submitting the specimen container - initials must be written across both the tape and the container
• Name of the submitting law enforcement agency
• Case number

To maintain the integrity of the specimen, a chain of custody should be initiated upon collection and the specimen should be refrigerated as soon as possible.

Result Reporting for DWI Testing

In suspected Driving While Intoxicated (DWI) cases, blood specimens first undergo alcohol testing. If the blood alcohol level is greater than or equal to 0.100 g/100 mL, no further testing is performed unless specifically requested. If the blood alcohol level is less than 0.100 g/100 mL, drug testing is performed.

Evidence Packaging

Gun Shot Residue Evidence

Fire Debris Evidence

• Fire debris evidence must be submitted in air tight containers, such as metal cans. Other forms of packaging, such as evidence bags, will not be accepted.
• Each item number should be packaged in a separate container.
  
  Note: Fire debris evidence is accepted only during business hours.

Firearms Evidence

• For safety reasons, firearms will only be received in clear plastic bags.
  • All firearms should be made safe by inserting a cable/zip tie in the action to render it inoperable.
  • Ammunition should be packaged separately from the firearm.
• The evidence submission form should clearly indicate the type of analysis that is being requested.
• Firearms may not be left in the after-hours drop box. Firearms may only be submitted in person between 7:30 a.m. and 4 p.m., Monday through Friday.
• Some circumstances, such as a firearm recovered from and submitted in water or a firearm that is loaded that cannot be made safe, will require special handling or attention. When this situation arises the Firearms Section should be notified directly so that appropriate accommodations can be made.

If additional clarification or assistance is needed please contact the Firearms Section at:
(832) 927-5190.

The Harris County Institute of Forensic Sciences Forensic Genetics Laboratory limits the initial number of samples for DNA testing based on the type of offense. Subsequent testing may be performed upon request as deemed necessary. 

Contact us for consultation at 832-927-5300.       
 

Felony Evidence Only
• Evidence from misdemeanor crimes is not accepted
  
  Sexual Assault
• Items in the Sexual Assault Kit are processed first 
• If informative DNA kit information is obtained, no further testing is needed 
• If DNA kit results are not informative, clothing and other items are processed sequentially
• All items will be processed in cases with multiple perpetrators
  
  Homicide
• Initial analysis is limited to 10 items selected by the investigator and/or the District Attorney’s Office
  
  Other Crimes Against Persons
• Initial analysis is limited to 5 items selected by the investigator and/or the District Attorney’s Office
  
  Property Crime
• Analysis is limited to 3 items selected by the investigator and/or the District Attorney’s Office
  
  Known Reference Samples
• Known standards submitted for analysis will not count against the number of items submitted for analysis for any type of case

Regular Business Hour Submissions
Monday through Friday
8 a.m. – 4 p.m.

• Non-DNA Specimens – Submit packaged evidence and a completed Evidence Submission Form at the Harris County Institute of Forensic Sciences’ Evidence Reception located at 1861 Old Spanish Trail, Houston, Texas 77054.
• DNA specimens – Submit packaged DNA evidence and a completed Evidence Submission Form at the Institute’s Forensic Genetics Laboratory located at 2450 Holcombe Blvd., Suite 7, Houston, TX 77021, in the John P. McGovern Campus of the Texas Medical Center.

• Non-DNA Specimens – Submit packaged evidence and a completed Evidence Submission Form at the afterhours evidence submission location, which can be accessed at the rear of the Institute’s building located at 1861 Old Spanish Trail, Houston, Texas 77054.

Click here for a vicinity map of the Institute's afterhours submission location.

• DNA specimens – Submit evidence at the Institute’s Forensic Genetics Laboratory at 2450 Holcombe Blvd., Suite 7, Houston, TX 77021, in the John P. McGovern Campus of the Texas Medical Center.

Click here for a vicinity map of the Institute’s Forensic Genetics Laboratory afterhours submission location.

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