If you are facing criminal charges, a skilled criminal defense attorney can defend you and argue your case in court. Having an attorney represent you can help you get a better plea bargain deal, get your charges dismissed, or get a "not guilty" verdict at trial. One way a criminal defense attorney will strengthen your defense is to challenge the evidence against you.

Ways an Arizona Criminal Defense Attorney Can Challenge the Admissibility of the Evidence

There are several ways an criminal defense attorney in Arizona can challenge evidence. In criminal courts in America, the prosecution cannot just use anything they want as evidence against you. There are rules of evidence that limit what can be used, and the prosecution has to follow those rules. The United States Constitution also places limitations on evidence that can be used in the government’s case against you.

Challenging the Admissibility of Irrelevant Evidence

One of the rules of evidence is that the evidence must be relevant to whether or not the defendant committed the crime. Evidence is considered relevant if it makes a fact that matters in the case more or less likely to be true.

For example, a defendant's taste in music would generally not be relevant to a theft case, as it has nothing to do with whether or not the defendant committed the theft. However, if a witness testifies that the thief drove away in a car that was blasting music from a certain band, then evidence regarding whether the defendant listened to that band would become relevant.

If evidence is wholly unrelated to a case, a criminal defense attorney can argue that it should not be admitted based on the rules of evidence. However, relevance is a very low standard, and it can be difficult for a criminal defense attorney to get evidence excluded based on lack of relevance alone.

Challenging the Admissibility of Relevant Evidence

A criminal defense attorney can also challenge the admissibility of evidence that is relevant if the evidentiary value of the evidence is substantially outweighed by a danger of one or more of the following:

Unfair Prejudice — This means that the evidence casts the defendant in such a poor light that it could lead the jury to reach its verdict based on the prejudice caused by that evidence alone and not the facts of the case.

Confusing the Issues or Misleading the Jury — This occurs when the evidence is relevant to more than one issue and at least one of the issues is not relevant.

Undue Delay, Wasting Time, or Needlessly Presenting Cumulative Evidence — This means that the evidence does not add enough value to the case to be worth the time it takes to present it, particularly when the fact it goes to show has already been proven through other evidence or a stipulation by the parties.

These types of evidentiary challenges tend to be more successful than those based solely on relevance because they allow evidence to be excluded even though it is relevant. A criminal defense attorney can challenge relevant evidence based on any of these factors, and the judge should exclude it if the value that the evidence adds to the prosecution's case is outweighed by one of these considerations.

Challenging Admissibility Based on Constitutional Violations

Finally, a criminal defense attorney can argue that evidence should not be able to be used against you if it was obtained through a violation of your constitutional rights. In the American criminal justice system, the police are not allowed to do whatever they want to get evidence. They need to follow certain rules and limitations put in place by the United States Constitution and the way that courts have interpreted the Constitution. To hold police officers accountable for violating people's constitutional rights, evidence that was illegally obtained can be suppressed—or excluded—from the case, and cannot be used against the defendant.

The following are common constitutional violations that a defense attorney can use to challenge the evidence against you:

The police unlawfully searched you and seized evidence.

An unlawful search and seizure occurs when the police search you and/or your property and seize evidence without a warrant or probable cause. If the police conducted an unlawful search and seizure, it is considered a violation of the Fourth Amendment, which protects Americans against “unreasonable searches and seizures.” A criminal defense attorney can argue that any evidence that was seized must be suppressed.

The police illegally stopped you, making your subsequent arrest invalid.

A traffic stop can also be conducted in violation of your Fourth Amendment rights against unreasonable searches and seizures if the police officer did not have a “reasonable suspicion” that you had committed, were committing, or were about to commit a crime. The police officer must be able to point to specific and articulable facts that add up to reasonable suspicion. If a traffic stop is found to be illegal, then any evidence the police collected as a result of the traffic stop must be excluded from the case.

The police did not give you the required Miranda warnings before questioning you.

Before interrogating a suspect, the police must provide the following Miranda warnings regarding the suspect’s rights:

“You have the right to remain silent. Anything you say can and will be used against you in a court of law. You have the right to an attorney. If you cannot afford an attorney, one will be provided for you. Do you understand the rights I have just read to you? With these rights in mind, do you wish to speak to me?”

If the police do not read you these warnings before interrogating you, it is considered a violation of your Fifth Amendment right against self-incrimination, and any evidence gathered from your interrogation can be suppressed.

The police coerced you into giving an involuntary confession.

An involuntary confession is an admission, of guilt that is not offered based on the suspect’s free will but is coerced by threats, torture, or a promise from the police. If a confession is involuntary, a criminal defense attorney can file a motion to suppress it based on multiple constitutional grounds. The use of an involuntary confession can be a violation of your Fourteenth Amendment right to due process, as well as your Sixth Amendment right to counsel.

The police used a witness identification procedure that violated your right to due process.

If the police officers used a prejudicial method of securing an out-of-court witness identification of the defendant as the person who committed the crime, a criminal defense attorney can challenge the admission of evidence of not only the out-of-court identification but of an in-court identification as well.

A Criminal Defense Attorney Can Help

An experienced Arizona criminal defense attorney can review the facts of your case and identify which pieces of evidence can be challenged as inadmissible. If the judge decides to exclude evidence against you, the prosecution may be willing to give you a better plea bargain offer, or, if they cannot prove their case against you without the evidence, dismiss your charges altogether.