Under United States criminal law, the prosecution must satisfy the legal standard of proving guilt beyond a reasonable doubt in order to successfully secure a conviction in a criminal case. Beyond a reasonable doubt is the highest standard of proof the prosecution must bear and requires them to present arguments and evidence such that there is no other reasonable explanation other than to return a guilty verdict.

Common Criminal Defenses Used By Lawyers

As the onus is on the prosecution to prove the charges, there is an inherent presumption of innocence toward the defendant. This fundamental principle supports the right of each individual to a fair trial. As a jury cannot convict a defendant of a crime if there is reasonable doubt as to their guilt the defendant’s lawyers must cast doubt on the evidence and allegations put forth by the prosecution.

This is the role that a Dallas Criminal Defense Lawyer and experts in criminal law will play to ensure their client is not wrongfully convicted of a crime. When it comes to defending their client, there are common defense strategies used by some of the best criminal lawyers to challenge and cast doubt on the prosecution’s case in order to get the charges against their client dismissed and to secure their freedom. In this article, we will take a closer look at some of those defenses.

Challenge Witness Credibility

The testimony of witnesses is often a key source of evidence in criminal cases and can help to establish the guilt or innocence of an individual. The defense can cast doubt on the credibility of prosecution witnesses and discredit their statements in a number of ways including:

  • Identifying Inconsistencies: A prior inconsistent statement can call into question the truthfulness or accuracy of their evidence.
  • History of Lying: Exposing a reputation for untruthfulness can be damaging to a witness’ credibility.
  • Impeachment by Bias: Establishing any hostility, prejudice, or interest for or against one of the parties can impeach a witness.

These are just some of the ways a defense lawyer can undermine the credibility of a witness.


The defense may use duress as a defense in certain situations arguing that the defendant was compelled to act unlawfully due to force or threat of immediate harm. To successfully use this defense, the following elements need to be established:

  • The defendant was under an immediate threat of serious bodily injury or death.
  • The defendant’s fear was well-grounded and they believed the threat would be carried out.
  • A reasonable person of the same gender and maturity would likely have acted in the same way when faced with the same threat.
  • The threat was continuing and the defendant had no reasonable opportunity to safely escape, except by carrying out the unlawful act.

If the court is convinced of these elements then duress can act as a defense for the defendant’s illegal act.

Constitutional Violations

A criminal defense lawyer may review the circumstances that led to their client’s arrest finding certain constitutional violations that can result in key evidence or a whole case against the defendant being dismissed by the judge.

Violations can include things like evidence being gathered without a search warrant deeming it inadmissible in court, or the police officer who arrested the defendant lacking reasonable suspicion or probable cause needed to justify their actions. The defense could also argue that the police continued to question their client after they asked for a lawyer or were simply denied legal representation.

Failure to read the defendant their Miranda rights during the arrest is another violation of their constitutional rights. This is to protect them from self-incrimination with the result that the prosecution cannot rely on their responses to custodial questioning as evidence at trial.


This is an example of an affirmative defense, meaning it is up to the defendant to prove the defense. In the case of an alibi, the defendant must prove they were not at the scene of the crime when it took place. By proving they were elsewhere at the time, this legal defense strategy ensures the defendant could not have committed the crime.

This requires supporting evidence from the defense such as witness testimony from a person or persons who claim to have been with the defendant at the time or surveillance footage that places them in an entirely different location from the scene of the crime.


Self-defense can be raised as a defense in cases like battery, assault and murder and allows a defendant to use justifiable force to protect themselves or another from the threat of harm or death even when their behavior would otherwise constitute a crime.

To successfully argue this defense, the defendant’s lawyer must be able to prove their client acted in response to an imminent threat of injury or death and their response was proportional to the level of the threat. The prosecution must also prove that the defendant reasonably believed force was necessary to defend themselves or others against imminent danger.

As highlighted in this article, the defense may employ several defenses to cast doubt on certain evidence or have the entire case against their client dismissed.