Defense Tactics in DRE cases

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Preparing for Trial: Common Defense Tactics in DRE Cases




Thomas E. Page

Los Angeles Police Department, retired




Deputy District Attorney Linda Condron

 Santa Clara County, California, District Attorney's Office


Thorough preparation, by both the prosecutor and the Drug Recognition Expert (DRE), is the key to providing effective testimony.  Preparing for trial includes anticipating the questions that the defense attorney will ask during cross-examination.


Following the direct examination by the prosecuting attorney, the defense counsel will typically challenge the Drug Recognition Expert's (DRE) opinion, and its basis, by posing the following types of questions to the DRE.  These questions are in addition to challenges to the officer's motivation, bias, completeness of reports, and so on. 


The Defendant is identified as Ms. Crystal Coral.


<          Missing Signs or Symptoms


This line of questioning attempts to elicit the fact that the defendant did not have all of the expected signs or symptoms of the drug (s) in question. 


Officer, you were taught that bruxism or grinding of the teeth is a sign of CNS Stimulant influence, isn't it?


Ms. Coral didn't have that sign, did she? 


REMARKS: It is rare indeed for an individual to display all of the classic effects of a drug.  The DRE's opinion is based on the totality of the observed signs and symptoms as elicited by the DRE evaluation. 


<          Point out what's Normal


The defense may also focus on those signs or symptoms that were normal, and were therefore, not consistent with influence by the drug in question.


Officer, you learned the normal range of temperature in DRE training, didn't you? 

And that range is 98.6 Fahrenheit plus or minus one degree, isn't it? 


You recorded Ms. Coral’s temperature as 98 degrees, didn't you? 


98 is within normal ranges, isn't it? 


Ms. Coral’s temperature was therefore normal, wasn't it?


Stimulants cause elevated temperature, don't they? 


Ms. Coral’s was not elevated, was it?


REMARKS:  Again, the defense focuses on the specifics, rather than the totality.  The DRE opinion is based on the totality of the presenting signs and symptoms.


<          Alternative Explanations


The defense elicits alternative explanations for the signs and symptoms of the drug (s) in question.  These alternative explanations usually deal with medical conditions, stress, a traffic collision, etc.


Officer, an elevated pulse rate can be caused by things other than drugs, can't it?


Excitement may cause it? 


Stress may cause it? 


Being involved in a traffic accident is stressful, isn't it? 


And being involved in a traffic accident may cause elevated pulse, right? 


Being interviewed in the early morning by three police officers is stressful? 


And that may also cause the pulse to be elevated, can't it?


REMARKS:  Certainly, any single sign or symptom can be caused by something other than drugs. The DRE, much like a medical doctor, focuses on the totality of the signs and symptoms.

<          Defendant's Normals


The defense attempts to emphasize the fact that not everyone is so-called normal, that normal is subjective.


Officer, you were taught the normal range for pulse in DRE training, weren't you? 


And you agree that not all people fall in that normal range, don't you? 


That there are people with pulse rates above normal that aren't on drugs, right? 


And that there are people with a pulse rate below normal that aren't on any drugs, right?  


A person's pulse changes over time, doesn't it? 


You don't know what Ms. Coral’s normal pulse is, do you? 


It could be in the normal range, right?


But her normal pulse, normal for her, could be above or could be below the so-called normal range, isn't that true?


REMARKS:  A vital sign that is out of the normal range doesn't mean that the person is under the influence of drugs.  A high or low vital sign must be considered in the overall context of the circumstances.


<          Doctor Cop


This line of questioning challenges the credibility of the officer's teachers - that they are police officers, rather than medical professionals. 


Officer, the teachers in this DRE school weren't doctors, were they? 


They weren't nurses either? 








They were police officers, right? 


REMARKS:  At a minimum, the instructors in a DRE course are certified  (certification issued by the International Association of Chiefs of Police) DREs who have completed an additional course of instruction to become a certified instructor. 


<          Just a Cop


This line of questioning challenges the DRE's credentials - that he or she is "just a cop."  This infers that the DRE evaluation is an ersatz medical evaluation that should be undertaken only by a medical professional.


Officer, you're not a doctor, are you? 


A toxicologist? 


A pharmacologist? 


A nurse? 


A physiologist? 


You don't have a degree in chemistry, do you? 


You're a police officer, right?


REMARKS:  Nobody is everything!  Even if the officer were also a medical doctor, the defense would probably point out that DRE belongs to the specialty of neurology!  The DRE has what few other professionals have - experience in encountering the drug-impaired person. 


<          The Unknown


By causing the officer to state that he or she doesn't know how a sign or symptom is caused, the defense attacks the officer's credibility.  This line of questioning challenges the officer's expertise, by implying that a real expert would know these things.


Officer, you don't know how stimulants dilate the pupil, do you? 


You don't know how alcohol supposedly causes nystagmus, do you? 


You don't know how stimulants supposedly elevate the heart rate, do you?


REMARKS:  This line of questioning also implies that "somebody" knows how the drugs produce all of their effects.  In fact, many drugs in the Physician's Desk Reference contain the statement: "The exact mechanism of action of this drug remains unknown." 



<          Guessing game


This tactic attacks the DRE opinion as a subjective guess, a belief, rather than an objective finding.  And guesses can be wrong.


Officer, your opinion in a DRE case is subjective, isn't it? 


It's really a belief on your part? 


You've made these beliefs in DRE cases in the past, haven't you?


And sometimes toxicology didn't find the drug you predicted, isn't that so? 


And, in fact, sometimes, toxicology didn't find any drug, isn't that so?


And so, sometimes your opinion is not correct, right? 


Sometimes, you guess wrong.


REMARKS:  Opinions, by nature, are subjective.   A psychiatric diagnosis, which is an opinion, for example, is based almost totally upon subjective criteria, as there is no urine test for schizophrenia.  A DRE's opinion, which is based upon both subjective and objective criteria, such as pulse rate, blood pressure, and the eye signs, is an opinion, which is "to a reasonable degree of certainty."  This is not a guess. Never agree with the suggestion that a DRE opinion is a guess.  


<          Others Say You’re Wrong


This tactic challenges the DRE’s knowledge by pointing out that other experts, including those in the government, may have different opinions.  This tactic sometimes backfires.


Officer, you are familiar with the U.S. Department of Justice, aren’t you?


And they support a good deal of research about drugs, don’t they?  They have a lot of experts?


The Department of Justice’s Bureau of Narcotics and Dangerous Drugs disagrees with some of what you say about drugs, right? 


That cocaine, for example, is not addictive?


REMARKS: The credible expert witness knows some of the history of his/her field.  The Bureau of Narcotics and Dangerous Drugs, the forerunner of the Drug Enforcement Administration, closed in 1973.  In 1973, many experts did honestly believe that cocaine was not addictive.  The addictive nature of cocaine became widely accepted in the 1980s, and has not been in dispute for many years.  The witness’s credibility is enhanced when he/she can point out that an organization cited by the defense no longer exists.


<          Guilt By Association


This tactic is an attempt to taint the DRE program by associating it with an admittedly controversial figure in law enforcement, former LAPD Chief, Daryl F. Gates.


Officer, the DRE program was started by the Los Angeles Police Department, wasn’t it?


And this DRE program started to grow and expand out of LA in the 1980s, right?


And, the Chief of the Los Angeles Police Department during that time was Daryl Gates, wasn’t it?


The Daryl Gates of Rodney King, O.J. Simpson, Mark Furman, right?


REMARKS:  Of course, the defense will never point out that it was the same Daryl Gates who sponsored the development of the DARE program, as well as many other innovations in law enforcement.  And by the way, Daryl Gates was not a DRE. 


A related defense tactic taints the witness’s credibility by mentioning a publicized scandal, such as the LAPD Rampart Division “corruption” scandal.


Officer, you work for the LAPD, don’t you?


Rampart Division perhaps?