Re-testing is a service designed to check the procedures and chain of custody of samples tested for the purpose of criminal prosecution (DUI, 11550, Probation violation, etc). It may also be done to check quantitative accuracy of samples previously tested by other laboratories.

DDL  provides sensitive and high quality quantitative determination of drugs or alcohol in biological fluids that is equal to, or surpasses, most laboratories that provide drug and alcohol testing for prosecutorial purposes (see ABOUT DRUG DETECTION LABORATORIES). Furthermore, DDL is staffed with forensic toxicologists who will qualify as experts in all aspects of the testing and interpretation of results.

TO REQUEST RE-TESTING: SEND A REQUEST (USUALLY WRITTEN) TO THE AGENCY WHICH HAS POSSESSION OF THE SAMPLE. In criminal cases, this is usually the district attorney's office. Request the specimen be shipped* to Drug Detection Laboratories at 9700 Business Park Drive, Suite 406, Sacramento, CA 95827. It is recommended that your request for referee retest to the District Attorney's laboratory included a request for a copy of the original chain-of-custody envelope and a copy of the label on the original vial.  We will forward copies of these documents to you with your retest report. Send a letter request or requisition form to DDL, along with payment for testing (see fee schedule).

* In the Sacramento area, specimens that are in possession of the Sacramento Crime Lab, Sheriff property, Police property, or Valley Toxicology lab will be picked up by DDL personally. There is an extra $25 fee to cover the split and/or transportation of these specimens. Specimens that must be picked up by DDL outside of Sacramento will require transportation fees of $1.25 per mile.

DRE Matrix/Pupilometers are available by contacting Drug Detection Laboratories at (916) 366-3113.