Chain of Custody Errors That Lead to Unreliable Lab Evidence

Forensic evidence is often portrayed as scientific proof that cannot be challenged. But in real criminal cases across Ohio, mistakes during evidence handling can compromise the reliability of lab results long before they reach a courtroom. Breakdowns in the chain of custody create serious legal problems because they raise questions about who handled the evidence, how it was stored, and whether it was altered or contaminated. Our Cleveland criminal defense lawyers at Patrick M. Farrell Co. L.P.A. represent clients throughout Cuyahoga County and Northeast Ohio in cases where faulty evidence procedures threaten to derail someone’s future. When the chain of custody is flawed, the entire case must be questioned.

Because prosecutors rely heavily on forensic evidence during arraignment, discovery, plea negotiations, and trial, exposing these errors is critical for building an effective defense strategy. Whether the allegation involves drugs, weapons, digital devices, or biological material, chain of custody failures can create reasonable doubt in the most serious cases.

What Chain of Custody Means in Ohio Criminal Cases

The chain of custody is the documented record of evidence from the moment it is collected until it is presented in court. This record must show:

• Who collected the evidence
• Where it was collected
• How it was packaged
• When it was transferred
• Who accessed it at each stage
• How it was stored

If any link in this chain is missing or improperly documented, the evidence may be unreliable. In the Cuyahoga County Common Pleas Court and Cleveland Municipal Court, judges expect prosecutors to prove that evidence has been preserved accurately and securely. When they cannot, the legal team at Patrick M. Farrell Co. L.P.A. challenges the admissibility of that evidence.

Common Chain of Custody Breakdowns

Breakdowns occur more often than the public realizes. Even small mistakes can create major doubt about what the evidence truly shows.

1. Improper Handling at the Crime Scene

The first few minutes after evidence is discovered are critical. Errors may include:

• Untrained officers collecting evidence
• Failure to wear gloves
• Placing multiple items in the same container
• Dropping, mishandling, or contaminating samples

These mistakes are often not documented, yet they can change the nature of the evidence itself.

2. Mislabeled or Unlabeled Evidence

A mislabeled bag or container is one of the most damaging errors in any criminal investigation. Common labeling problems include:

• Items placed in the wrong evidence bag
• Incorrect case numbers or dates
• Illegible handwriting
• Missing initials or identifying marks

When labels do not match reports, it becomes impossible to confirm that the evidence presented in court is the same evidence collected at the scene.

3. Storage Errors That Affect Integrity

Ohio law enforcement agencies must store evidence in controlled environments. However, storage mistakes are common and include:

• Refrigerated evidence stored at room temperature
• Wet biological samples placed in sealed containers that encourage mold
• Drug samples stored with incompatible substances
• Evidence left in unsecured rooms or vehicles

Even slight changes in temperature or humidity can alter forensic results.

4. Breaks in Documentation

Every evidence transfer requires detailed paperwork. Missing or incomplete logs raise immediate concerns. These gaps may involve:

• Undocumented transfers
• Evidence moved without authorization
• Logs that conflict with testimony
• Long periods where the location of evidence is unknown

Without clear documentation, prosecutors cannot prove the evidence remained unaltered.

5. Contamination in Crime Labs

Once evidence reaches a lab, it must be handled according to strict scientific protocols. Contamination occurs when:

• A lab technician uses unclean tools
• Samples are placed too close together
• Containers are reopened improperly
• Lab equipment is not calibrated or maintained

Inaccurate results from poor lab practices can lead to wrongful arrests and convictions.

6. Mixed or Compromised Samples

In cases involving DNA, drugs, or chemical testing, evidence is often divided into multiple samples. Problems arise when:

• Samples are mixed
• Comparison samples are mislabeled
• Instruments detect residue from previous tests

These mistakes can make it impossible to tell which sample belongs to whom, and these types of DNA testing errors can undermine the integrity of the entire case and cast doubt on the accuracy of the lab’s conclusions.

How Chain of Custody Problems Affect Criminal Charges

When the chain of custody is flawed, forensic results may be invalid or misleading. This undermines the reliability of evidence used for:

• Drug charges under O.R.C. § 2925
• OVI cases involving blood or urine tests under O.R.C. § 4511.19
• Weapons cases relying on fingerprints or DNA
• Assault and sex offense cases built on biological evidence
• Property crimes involving digital devices or stolen items

Because prosecutors rely heavily on forensic results, chain of custody errors create opportunities to suppress evidence or negotiate reduced charges.

How Investigators Use Evidence Despite Errors

Even when the chain of custody is weak, investigators may still attempt to use the evidence to:

• Support arrest warrants
• Obtain search warrants
• Pressure defendants during plea negotiations

The legal team at Patrick M. Farrell Co. L.P.A. scrutinizes every step of the state’s process to ensure unreliable evidence is not treated as scientific fact.

How Patrick M. Farrell Co. L.P.A. Challenges Unreliable Evidence

Our defense strategies focus on exposing weaknesses the prosecution does not want the court to see. Common methods include:

• Challenging undocumented transfers
• Highlighting inconsistencies in labeling
• Filing motions to suppress compromised samples
• Questioning lab technicians about contamination risks
• Examining storage logs and environmental conditions
• Presenting expert testimony on forensic procedures

If you're looking for a Cleveland criminal defense lawyer near me who understands how easily evidence can be mishandled, our firm brings the experience needed to expose these mistakes and protect your rights.

Chain of Custody Errors Can Change the Outcome of a Case

Forensic evidence plays a significant role in criminal prosecutions, but its accuracy depends entirely on proper handling from beginning to end. When the chain of custody breaks, evidence may no longer reflect the truth. The legal team at Patrick M. Farrell Co. L.P.A. represents clients in Cleveland, Lakewood, and throughout Northeast Ohio with a strong commitment to challenging compromised evidence and ensuring fairness in the criminal process. Your future should never depend on evidence that was mislabeled, mishandled, or contaminated.

If you’ve been arrested in Cleveland, Lakewood, or anywhere in Northeast Ohio, don’t wait. Call Patrick M. Farrell Co. L.P.A. at (216) 661-5050 or request a free consultation now. When evidence is flawed, the right defense can make all the difference.

Text or Call: (216) 661-5050 • Contact: Submit a Request • Email: cindy@patfarrelllaw.com

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