DWI/DUI – Objecting to Lab Results; Preserving Blood/Urine Sample; Challenging Chain of Custody


Challenging blood evidence is not as scary as one may think.  This article is intended to give attorneys a blue print on how to notify the State of your intention to challenge blood/urine evidence, blood/urine lab results and the chain of custody of all evidence in your case.  It is a must in all DWI/DUI cases dealing with bodily fluid.  Great criminal defense attorneys never leave any stones unturned when advocating for their client.  The best attorneys don’t stipulate anything to speed up a trial.  Why help the prosecution if they are unwilling to help you.  Make them earn it.  The following paragraphs should be incorporated in a letter format and sent to the prosecutor pursuant to a terms set forth in a case management order, if applicable. 

Dear Mr. _______________, 

I represent the defendant, ___________________, in the above entitled action.  Please be advised that I am still awaiting initial discovery in this matter.  I hereby give notice to the State of my intent to object and challenge the following matters at trial or through pre-trial motions: 

     1.  Chain of custody of all blood, urine and/or breath samples taken from defendant;

     2.  Chain of custody of all evidence taken from defendant;

     3.  Pursuant to N.J.S.A. 2C-35-19, I object to admissibility of the at-issue lab                               certificate(s) and lab report(s). 

Please take further notice that I intend to confront and challenge the lab technician(s) and/or scientists who performed and certified the lab results of defendant’s blood, urine and/or breath. 

Please take further notice that I intend to confront and challenge any and all custodian(s) of evidence in this matter. 

Pursuant to N.J.S.A. 2C-35-19, please provide me with a copy of the request for examination of evidence; all reports and notes prepared by the scientist; the underlying data used to reach conclusions concerning the composition and quantity of the substance submitted for examination, and any graphs, charts or computer printouts that describe the results of any manual or automated test of the substance submitted for examination. 

Pursuant to N.J.S.A. 39:4-50(c) and (d), I demand the State preserve and produce the unused portion of defendant’s blood and/or urine.  The defendant seeks to obtain independent testing and analysis of same. 

Lastly, please provide copies of all drug recognition certifications for the arresting officer or any other officer involved in the defendant’s arrest.

                                                                    Very truly yours,

Now the State has to produce any and all parties who took the blood/urine sample and tested it.  Additionally, the State must preserve any unused portion of the sample taken from your client.  Very often, the State cannot produce these witnesses at trial and/or they fail to preserve the bodily fluid.  As a result, the test results must be thrown out.

Don’t get intimidated by challenging evidence.  It is your duty to do everything possible to defend your client.



Source by Jay M. Arnesen