The Constitution gives you the right to confront the witnesses against you. In a blood case, one of the most important witnesses is the analyst who ran the test on the instrument. The State does not always bring that person to court. Sometimes it sends a supervisor or a reviewer who can describe the lab’s procedures in general but did not perform your analysis. The Confrontation Clause has a lot to say about that substitution, and recent law has made the right stronger.
This is one of the sharpest tools in a blood defense, because it is not about whether the science is good or bad. It is about who has to take the stand and answer for it. If the State wants to put a number in front of a jury, the person who produced that number should be the one facing cross-examination.
A reviewer can describe the lab in general terms, but the right to confront points to the analyst who did the work.
The Right to Confront the Witness Against You
The Sixth Amendment guarantees that a defendant can confront the witnesses against him. In Crawford v. Washington, 541 U.S. 36 (2004), the Supreme Court held that testimonial statements made out of court cannot be used against a defendant unless the person who made them is unavailable and the defendant had a prior chance to cross-examine them. A lab analyst’s formal statements about a test, prepared for use in a prosecution, are exactly the kind of testimonial statements Crawford was concerned with.
A Lab Report Is Testimony
The Court applied that principle to forensic evidence in Melendez-Diaz v. Massachusetts, 557 U.S. 305 (2009), holding that a forensic laboratory certificate is testimonial. The State cannot simply hand the jury a signed lab document in place of live testimony. The analyst is a witness, and the defendant has the right to make that witness take the stand and answer questions under oath. A blood alcohol result is not exempt from this rule because it comes from an instrument.
A Stand-In Will Not Do
The State’s next move was to send a different analyst, one who could speak to the lab’s procedures but had not performed the test. The Supreme Court addressed that in Bullcoming v. New Mexico, 564 U.S. 647 (2011), holding that the Confrontation Clause is not satisfied by a surrogate analyst who did not perform or observe the testing standing in for the one who did. The witness who certifies the result has to be the witness who made it, because only that person can be cross-examined about what happened during the analysis.
Smith v. Arizona Closes the Loophole
After Bullcoming, prosecutors tried another path: have an expert offer an opinion that relied on the absent analyst’s work, and claim the analyst’s statements were not admitted for their truth but only as the basis for the expert’s opinion. The Supreme Court rejected that workaround in Smith v. Arizona, 602 U.S. 779 (2024). The Court held that when an expert conveys an absent analyst’s statements to support the expert’s own opinion, and those statements support the opinion only if they are true, then they are being offered for their truth and the Confrontation Clause applies. That decision sharply narrows the ability of a substitute witness to read in the testing analyst’s work.
From Crawford to Smith v. Arizona, the Supreme Court has steadily closed the routes around confronting the analyst who did the work.
Why This Matters in a Blood Case
In Florida DUI blood cases, the result often passes through more than one set of hands, with one analyst running the instrument and another reviewing or certifying the file. When the State brings only the reviewer, the defense can insist on the person who performed the analysis. The analyst who ran the gas chromatography is the one who can be asked about the chromatogram, the calibration, and the run that day. A surrogate cannot answer for choices they did not make and a test they did not perform.
What We Do
We identify exactly who performed each step of the analysis, compare that to who the State intends to call, and object when the State tries to substitute a witness who did not do the work. Paired with the technical review of the data, this turns the cross-examination into a direct confrontation with the person responsible for the number, which is what the Constitution promises.
A blood case often rests on the word of an analyst who never comes to court, and I do not let the State hand me a stand-in. If the person who ran your test is not on the stand, I press the point the Supreme Court has now made three times, that a lab report is testimony and its author is a witness you are entitled to confront. When the State cannot produce that analyst, or tries to slide the result in through someone who only read the file, that is a constitutional problem, not a technicality, and I make the court treat it as one.
I started out as an Assistant Public Defender in Florida’s Thirteenth Judicial Circuit, in Tampa, and today I am one of six ACS-CHAL Forensic Lawyer-Scientists in Florida. I work both the science and the procedure in your case the way the State’s own analysts and officers are trained to, and I show a jury the exact point where the evidence does not hold up. Learn more about my background.
Questions About the Non-Testing Analyst
Who has to testify about my blood test?
The analyst who performed the test. Under the Confrontation Clause, the witness who produced the result is the one the defense has the right to cross-examine, not a stand-in who only reviewed the file.
Can the State just submit the lab report?
No. Melendez-Diaz v. Massachusetts holds that a forensic lab certificate is testimonial, so the State cannot hand the jury a signed document in place of live testimony from the analyst.
Can a different analyst stand in for the one who tested my blood?
Generally not. Bullcoming v. New Mexico holds that a surrogate who did not perform or observe the testing cannot satisfy the right to confrontation in place of the analyst who did.
What did Smith v. Arizona change?
It closed a workaround. The Court held that when an expert relays an absent analyst’s statements to support the expert’s opinion, and those statements support the opinion only if true, they are offered for their truth and the Confrontation Clause applies. That narrows the use of a substitute witness.
Why does this matter if the science is sound?
Because it is about process, not just accuracy. Only the analyst who did the work can be questioned about what happened during your test. The right to confront that person is independent of whether the result looks reliable.
How do you raise this in my case?
We determine who performed each step, compare it to who the State plans to call, and object to any substitution of a witness who did not do the work, while pairing it with a technical review of the data.
Related: gas chromatography, lab accreditation, calibration, how we challenge a blood test, and the blood test overview.
Does the analyst who tested my blood have to testify?
The analyst behind the result is a witness you have the right to confront. Under Melendez-Diaz, a lab report is testimony; under Bullcoming, a surrogate who did not perform the test cannot stand in; and under Smith v. Arizona in 2024, an expert cannot relay another analyst’s results as the basis for an opinion. A stand-in reading the file is not enough.
This page is general information, not legal advice, and it does not create an attorney-client relationship. The right of confrontation arises under the Sixth Amendment, as interpreted in Crawford, Melendez-Diaz, Bullcoming, and Smith v. Arizona. Procedures and rules change, and every case turns on its own facts. Past results do not guarantee a similar outcome.
