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Prosecutors who handle New Jersey driving while intoxicated (DWI) cases must prove that a defendant is guilty beyond a reasonable doubt. They present evidence in order to establish that a defendant was under the influence of alcohol or drugs. In order to counter this evidence, a defendant may need to produce an expert witness. A compelling report from an expert could even convince a prosecutor to drop a DWI charge. If not, the expert can testify at trial about their findings. An experienced DWI defense lawyer can identify where expert testimony would be most helpful and can find qualified experts for your case.

What Is an Expert Witness?

Rule 702 of the New Jersey Rules of Evidence (NJRE) defines an expert witness as someone who has particular “scientific, technical, or other specialized knowledge,” which they have attained through “knowledge, skill, experience, training, or education.” This definition has three important components:
1. The subject must be beyond many or most people’s understanding.
2. The witness’ field of expertise must be established enough to provide reliability.
3. The witness must demonstrate that they have achieved expertise in the field.
Unlike other witnesses, expert witnesses may testify about their opinions, as long as those opinions are based on their expert knowledge and can help a judge understand a DWI case.

A police officer with training in the use of Alcotest devices, for example, may testify about the condition and reliability of the machine used to test samples of a defendant’s breath. A drug recognition expert (DRE) could testify about their conclusion, based on training and experience, that a defendant was under the influence of a particular drug or type of drug.
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In order to prove guilt in driving while intoxicated (DWI) cases in New Jersey, law enforcement must show that a defendant was under the influence of either alcohol or certain types of drugs. State law allows them to use chemical tests that allegedly show the presence of alcohol or drugs. Chemical testing for alcohol has an extensive body of law addressing how police must collect and test samples of a DWI suspect’s breath. For other drugs, they must use samples of blood or urine. This type of testing can be much less certain, both scientifically and legally. Urine testing, in particular, has significant reliability issues. If the state tries to introduce results from urine tests, DWI attorneys must carefully examine the evidence to look for errors.

New Jersey has used chemical testing in DWI and DUID cases for decades. In 1964, the New Jersey Supreme Court held that “[a]lcoholic content in the blood furnishes a scientific measure of the extent of the influence of liquor upon the person.” It went on to state that “chemical analysis of the blood itself, urine, breath and other bodily substances is a scientifically accurate method of ascertaining that content.”

State law currently defines the offense of DWI in two ways: “operat[ing] a motor vehicle” either (1) while impaired by an “intoxicating liquor, narcotic, hallucinogenic or habit-producing drug;” or (2) “with a blood alcohol concentration [BAC] of 0.08% or more by weight of alcohol in the defendant’s blood.” BAC above the “legal limit” of 0.08% creates a presumption that the defendant is legally impaired by alcohol. The state’s implied consent statute makes breath testing mandatory in DWI investigations.
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When a person is charged with driving while intoxicated (DWI) in New Jersey, they have two main options for how to respond to the state’s charges. They can enter a guilty plea, or they can fight the charges and go to trial. A defendant might plead guilty to DWI for numerous reasons. A guilty plea can be a way of avoiding worse penalties after a trial. Defense attorneys can negotiate with prosecutors in many cases in a process known as “plea bargaining.” Plea agreements often involve a defendant pleading guilty in exchange for a lighter sentence or dismissal of some charges. DWI cases, however, are different. Rules established by the New Jersey Supreme Court limit prosecutor’s ability to enter into plea agreements in cases involving DWI and refusal to submit to breath testing. Read on to learn more about what issues are subject to negotiation with prosecutors in New Jersey DWI cases.

What Is a Plea Agreement?

After a defendant first appears in court on a motor vehicle charge, some time will pass before the court will set the case for trial. Defendants and defense attorneys often use that time to negotiate with prosecutors. This process is somewhat similar to negotiations between opposing attorneys in civil lawsuits, with the goal being to resolve the dispute without going to trial.

A good plea agreement often leaves both sides feeling like they got something, but neither side feeling like they “won.” Prosecutors give up the chance of a guilty verdict, and defendants admit to some part of the state’s charges. In a case involving a reckless driving charge, for example, a defendant might agree to:
– Plead guilty to a lesser offense, like careless driving, in exchange for dismissal of the more serious charge; or
– Plead guilty to the charged offense in exchange for the prosecutor’s recommendation for a lesser sentence.
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New Jersey’s driving while intoxicated (DWI) statute is not limited to alleged driving while under the influence of alcohol. The law only provides an actual metric for how much alcohol may be present in someone’s system before they are presumed to be legally impaired. For cases involving alleged impairment by other substances, New Jersey prosecutors often rely on drug recognition experts (DREs), law enforcement officers who have received training that purports to help them identify the effects of particular drugs on individuals. After a DWI defendant challenged the admissibility of DRE evidence, the New Jersey Supreme Court appointed a special master to assess each step in the procedure used by DREs. Evan Levow is representing the DUI Defense Lawyers Association (DUIDLA) in the case. A hearing began in early October 2021, in which the special master is hearing testimony regarding the scientific reliability of DREs. With New Jersey moving towards the legalization of recreational cannabis, the outcome of this case is likely to have a far-reaching impact.

In addition to alcohol, the DWI statute includes “narcotic[s], [and] hallucinogenic or habit-producing drug[s]” as substances that can cause impairment. A driver with blood alcohol content (BAC) of 0.08 percent or more is subject to a presumption of impairment. The statute does not specify actual amounts of any other substance. Instead, prosecutors must introduce eyewitness testimony about a defendant’s behavior to prove that they were too impaired to drive. DREs arose as a way for the state to meet its burden of proving impairment.

DREs receive training and certification based on the Drug Recognition and Classification Program (DEC), which is operated by the International Association of Chiefs of Police and the National Highway Transportation Safety Administration. The DEC protocol involves a twelve-step process that DREs use to evaluate individuals suspected of driving under the influence of drugs (DUID). The process begins with BAC testing, and includes field sobriety tests and various other examinations. Toxicology testing is the last step in the process.

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Driving while intoxicated (DWI) is a serious offense under New Jersey law. A conviction can result in a fine, driver’s license suspension, jail time, and other penalties, depending on various factors. DWI attorneys work hard to make sure the state follows the law and respects their clients’ rights. If a case goes to trial, and the court convicts the defendant of DWI, they may still be able to keep fighting the charges by filing an appeal. New Jersey law requires a defendant appealing a DWI conviction, also known as the “appellant,” to cite specific grounds for the appeal. It is not enough that the appellant is not happy with the outcome of the trial. They must show that the court made an error, or that the process was flawed.

Appeals Based on the Evidence

In any DWI case, the prosecution has the burden of proving the defendant’s guilt beyond a reasonable doubt. This is the strictest burden of proof in our legal system. A prosecutor’s job is supposed to be difficult, since success for a prosecutor could mean a loss of freedom for a defendant.

A DWI appellant can argue that the state did not produce enough evidence to support a guilty verdict. Prosecutors must have evidence of guilt beyond a reasonable doubt for every element of the offense. A Law Division court, which hears appeals of DWI verdicts from municipal courts, could find that the state’s evidence was insufficient to meet the prosecutor’s burden of proof.
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In New Jersey, driving while intoxicated (DWI) is a serious offense that can carry significant penalties. A DWI defense attorney’s job is to advocate for and protect their client’s rights with both prosecutors and the court. Often, we are able to get a DWI charge reduced to something less serious, or even dismissed altogether. A conviction is not necessarily the end of a case, though. A defendant who has been convicted of DWI might have several options for continuing to fight for their rights.

How DWI Convictions Happen

Before discussing a DWI defendant’s options after a conviction, it is important to understand how convictions occur. In New Jersey DWI cases, a conviction can happen when:
– A defendant pleads guilty; or
– A municipal court judge finds the defendant guilty after a trial.
A defendant can enter a conditional guilty plea, which allows them to appeal the verdict on certain grounds.

Post-Conviction Relief

Appealing a conviction is not the only way to continue fighting. Post-conviction relief (PCR) gives defendants an opportunity to challenge a conviction in the same municipal court that found them guilty.
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In any case involving alleged driving while intoxicated (DWI) in a New Jersey municipal court, the state must prove the defendant’s guilt beyond a reasonable doubt. The New Jersey Rules of Evidence establish what kinds of evidence courts may consider, and what attorneys must do to get their evidence admitted. Testimony from various witnesses occurs in every trial. An important limitation on testimony during a trial is known as the “hearsay rule.” You may have heard this term if you watch any lawyer shows on television. What does the hearsay rule actually do, though? The following is an overview of the hearsay rule, and how it can help both sides in different ways in New Jersey DWI cases.

Evidence in New Jersey DWI Cases

New Jersey’s DWI statute allows prosecutors to prove that a defendant was impaired by alcohol or drugs in two ways. Both require testimony.

The state can have the arresting officer testify under oath about the defendant’s behavior or appearance at the time of their arrest. Perhaps, for example, the defendant was slurring their speech, or had bloodshot eyes.
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New Jersey’s laws dealing with the offense of driving while intoxicated (DWI) say a great deal about impairment by alcohol, but far less about impairment by other substances. The statute makes it a motor vehicle offense to drive “while under the influence” of alcohol, with blood alcohol concentration (BAC) of 0.08 percent, or while under the influence of a “narcotic, hallucinogenic or habit-producing drug.” This last category is ill-defined, especially when compared to the vast body of law dealing with alcohol. New Jersey courts may accept testimony regarding impairment by drugs even in the absence of evidence of any specific drug in a sufficient amount to cause impairment. Understanding how New Jersey law deals with “drugged driving” is critical to mounting a defense.

State law identifies two types of DWI involving alcohol. Operating a vehicle while “under the influence of alcohol” constitutes DWI, but requires the state to prove the existence of alcohol’s “influence” over a defendant. If a defendant had BAC of 0.08 percent or more, state law presumes that they were under the influence. This is known as DWI per se. Courts have developed an extensive set of rules surrounding DWI allegedly caused by alcohol, especially when breath testing is involved.

We were part of a landmark 2008 decision by the New Jersey Supreme Court, State v. Chun, which established procedures and requirements for the admissibility of BAC evidence obtained from breath testing. It addressed the breath-testing device used by law enforcement around the state, known as the Alcotest. The state supreme court has reiterated the importance of the procedures set forth in Chun. In a 2015 decision, for example, it stated that any finding of guilt in a DWI per se case “is subject to proof of the Alcotest’s reliability.”
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Police and prosecutors can use blood alcohol content (BAC) evidence to prove that a defendant charged with driving while intoxicated (DWI) in New Jersey was under the influence of alcohol. State law presumes that a person was too impaired to drive safely if their BAC was 0.08 percent or higher. Evidence of BAC at or above this “legal limit” does not automatically mean, however, that the state has met its burden of proving guilt. When police are not able to conduct breath testing for BAC, such as when a driver suspected of DWI must go to the hospital after an accident, they might test a sample of the person’s blood instead. Blood testing presents different challenges for police, and opportunities for defendants to dispute the evidence against them.

Breath vs. Blood Testing

The New Jersey DWI statute uses very broad language to define the offense and state what kind of evidence the state may use to prove that a person was “under the influence of” alcohol. State and federal courts have filled in many details regarding the collection of breath, blood, or urine samples to test for BAC. Police throughout New Jersey use a device called the Alcotest to test breath samples at police stations. The device analyzes the breath sample and reports results in a few moments.

A medical professional must draw a blood sample for BAC testing. This usually occurs at a hospital. The sample must then be transported to a laboratory. Prosecutors must show a clear chain of custody for the sample, and they must be able to establish that no contamination occurred at any point.
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New Jersey prosecutors can prove guilt in driving while intoxicated (DWI) cases by presenting evidence showing beyond a reasonable doubt that a person was impaired by alcohol or drugs while operating a vehicle. They can also prove guilt, at least with regard to impairment by alcohol, by showing that a person’s blood alcohol content (BAC) was at least 0.08 percent. Police can measure BAC using samples of a person’s breath or blood. For drugs other than alcohol, they must test blood or urine. Drug testing is far from a settled science, and false positives still occur quite often. DWI defense in New Jersey requires careful examination of evidence that supposedly shows positive drug test results or BAC above the “legal limit” of 0.08 percent.

State law requires drivers to submit breath samples for BAC testing. Anyone driving on New Jersey’s public roads is considered to have consented to breath testing. Refusal to submit breath samples is a motor vehicle offense that could be charged along with DWI. Blood and urine samples still require either a search warrant or a driver’s consent.

Police in New Jersey use a device known as the Alcotest to test breath samples for BAC. Unlike blood or urine samples, breath samples cannot be stored for later testing. The Alcotest is therefore designed to perform tests at police stations, not laboratories. A person blows into a tube, and the device subjects the breath sample to chemical reactions. The device requires frequent maintenance and careful calibration.
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