Intriguing Third Circuit panel ruling rejects drug quantity finding based on extrapolation

I have long been troubled by how much weight the US Sentencing Guidelines give to drug quantities in guideline calculations, in part because of how those quantities are sometimes calculated.  A recent Third Circuit panel decision provide a small window into these stories in the course of finding insufficient how federal prosecutors sought to prove up drug quantities in the sentencing of a hinky doctor.  Here is how the opinion in US v. Titus, No. 22-1516 (3d Cir. Aug 22, 2023) (available here):

Though the prosecution bears a heavy burden of proof, we will not let it cut corners.  Dr. Patrick Titus wrote thousands of prescriptions for controlled substances.  The government properly proved that many of these prescriptions were unlawful, so we will affirm Titus’s conviction.  But many other prescriptions were lawful.  And the severity of Titus’s sentence depended on how many were not.  Rather than review every patient’s file, the government urged the court to extrapolate from a small sample.  Yet the government failed to show that doing so would satisfy its burden to prove the drug quantity by a preponderance of the evidence.  Because the court sentenced Titus without enough proof, we will vacate his sentence and remand for resentencing.