Criminal Sexual Conduct (CSC) cases in Minnesota are among the most serious and complex criminal charges a person can face. Prosecutors rely heavily on scientific and medical evidence to build these cases, including DNA testing and Sexual Assault Nurse Examiner (SANE) exams.
While DNA and SANE evidence may sound conclusive, it is not always as clear or reliable as it seems. Errors in collection, testing, and interpretation can lead to wrongful accusations or convictions. Understanding how these forms of evidence work—and how they can be challenged—is critical to protecting your rights.
At Martine Law, we defend people accused of sexual offenses throughout Minnesota, helping them understand the evidence against them and building strategic defenses to expose weaknesses in the prosecution’s case.
Understanding DNA and SANE Evidence in Minnesota CSC Cases
What is DNA evidence?
DNA evidence refers to biological material such as blood, semen, skin cells, or saliva that can link a suspect to a crime. In CSC cases, DNA is often collected from:
- The alleged victim’s body or clothing
- Bedding, furniture, or personal belongings
- Items collected during a SANE exam
Labs analyze this material using profiles to determine whether a suspect’s DNA matches the sample found.
What is a SANE exam?
A Sexual Assault Nurse Examiner (SANE) exam is a medical forensic examination performed by trained nurses after a reported sexual assault. These exams are conducted following Minnesota Statutes §609.35, which allows for the collection of physical evidence to aid criminal investigations.
A typical SANE exam may include:
- A detailed interview with the alleged victim
- Collection of DNA evidence through swabs and samples
- Documentation of physical injuries
- Photographs and written notes
- Chain-of-custody transfer of all evidence to law enforcement
SANE exams can play a major role in shaping how prosecutors and juries view a case—but they are not infallible.
Common Problems With DNA Evidence
Even when handled by professionals, DNA evidence can be contaminated, misinterpreted, or overstated. Common issues include:
- Contamination or mishandling
DNA can be transferred through everyday contact—hugging, touching surfaces, or sharing spaces. Improper storage or handling can also lead to cross-contamination. - Partial or mixed samples
Many samples collected in sexual assault cases contain DNA from multiple people. Interpreting mixed DNA samples requires assumptions that can easily be challenged by a skilled defense attorney. - Laboratory errors
Testing procedures rely on human input. Mistakes in labeling, analysis, or statistical calculation can produce false matches. - Transfer DNA
DNA does not always prove direct contact. For example, someone’s DNA can appear on an object simply because another person carried or touched that object afterward.
If DNA evidence plays a key role in your case, a defense lawyer can request independent testing or call upon forensic experts to review the state’s methods and results.
How SANE Exams Can Be Challenged
SANE nurses provide vital care to victims, but their reports are often treated as if they prove guilt—when they do not. SANE exam findings must be interpreted carefully, and defense attorneys can challenge them on several grounds:
- Subjective observations
SANE nurses are not forensic scientists or detectives. Their notes often rely on the alleged victim’s account, which may include inconsistencies or memory gaps. - Lack of correlation between injury and assault
Many SANE reports note redness, irritation, or tearing. However, medical studies show that such findings can occur in consensual sexual activity as well. The absence of injury also does not mean no assault occurred, making the reports scientifically limited. - Chain-of-custody issues
Each piece of evidence collected during a SANE exam must be properly sealed, labeled, and documented. Any break in the chain of custody can make that evidence inadmissible. - Exam timing
The reliability of evidence decreases significantly as time passes between the alleged assault and the exam. Delayed testing can lead to contamination, degradation, or misinterpretation.
Bias in documentation
Some SANE nurses may unconsciously write in a way that supports the alleged victim’s account rather than presenting purely objective findings. This can be exposed through cross-examination and expert testimony.
Strategies to Challenge Forensic Evidence in CSC Cases
A Minnesota criminal defense attorney can use several strategies to question DNA and SANE evidence, including:
- Filing motions to suppress evidence if testing violated the Fourth Amendment or due process rights.
- Requesting independent laboratory review to verify or dispute the results.
- Cross-examining the forensic expert to reveal weaknesses or lack of certainty.
- Highlighting the absence of direct proof of assault, since DNA only shows physical contact, not consent or intent.
- Using expert witnesses in forensic science or medical examination to educate the jury on the limitations of such evidence.
Every case is unique, and the right strategy depends on how evidence was collected, preserved, and presented.
Why Hiring a Defense Lawyer Early Matters
Forensic evidence is often presented as conclusive, but a skilled lawyer knows how to uncover its flaws. Early intervention allows your attorney to:
- Obtain copies of all lab reports and chain-of-custody documents.
- Request a court order for independent DNA testing.
- Identify inconsistencies between the SANE report and police statements.
- Prevent the prosecution from overstating scientific certainty to the jury.
At Martine Law, we know how Minnesota courts handle CSC cases and what it takes to challenge flawed or incomplete forensic evidence. Our team works with independent experts to scrutinize every test and expose weak points in the state’s case.
Protecting Your Rights After a CSC Charge
If you are under investigation or have been charged with Criminal Sexual Conduct in Minnesota, do not assume that DNA or medical evidence automatically proves guilt. You have the right to question the evidence, demand fairness, and present your own expert testimony.
Contact Martine Law today to speak with an experienced Minnesota sex crimes defense attorney. We will help you understand your rights, review every piece of evidence, and fight for your freedom and reputation.