People of Guam v. Joshua Brandon Perez, 2021 Guam 18

In Dec. 2018 police stopped Joshua Perez for erratic driving and found ~0.5 g methamphetamine (baggies and residue), glass pipes, scales, lighters, and a book titled Secrets of Methamphetamine Manufacture.
Perez was indicted for Possession with Intent to Deliver and Possession (Schedule II); a Notice alleged Commission of a Felony While on Felony Release based on an earlier pending attempted burglary charge.
A jury acquitted Perez of possession with intent to deliver but convicted him of simple possession; Perez moved for judgment of acquittal arguing the People failed to prove methamphetamine is an “amphetamine‑based substance.”
Before the Apprendi (sentence‑enhancement) hearing, Perez signed a written waiver of his Apprendi/jury rights after previously declining; the court accepted the waiver and dismissed the jury.
The prior felony (the release-triggering charge) was later dismissed; nonetheless the court imposed a consecutive five‑year enhancement for committing a felony while on felony release and one year for the possession, for a six‑year aggregate sentence.
On appeal Perez challenged (1) sufficiency of the evidence that methamphetamine is an amphetamine‑based substance, (2) validity of his Apprendi/jury‑trial waiver, and (3) legality of the five‑year enhancement after dismissal of the underlying charge. The Supreme Court of Guam affirmed.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Validity of Apprendi/jury‑trial waiver	Waiver was written, defendant was informed in court, and no coercion; written waiver creates presumption of validity	Waiver was signed only after repeatedly declining; signature alone insufficient; court failed to ensure waiver was knowing and intelligent	Waiver was valid: totality of circumstances shows Perez knew consequences, no special disadvantage, and court/Govt consented; court did not err in accepting the written waiver
Sufficiency: methamphetamine = “amphetamine‑based substance”	Circumstantial evidence (presumptive field tests, officer ID, the book introduced at trial) suffices to identify the drug	Title of the book alone and non‑expert testimony were inadequate to prove methamphetamine is amphetamine‑based	There was proof of possession of methamphetamine; court took judicial notice that methamphetamine is an amphetamine‑based substance and held the evidence sufficient
Legality of 5‑year enhancement after underlying charge dismissed	Statute punishes committing a felony while on release regardless of outcome of the earlier charge; enhancement penalizes the second offense and betrayal of court trust	Enhancement improper because the underlying felony was dismissed (or defendant acquitted)	Enhancement valid: statute applies based on fact of being on felony release when committing a new felony; outcome of the prior charge is irrelevant

Apprendi v. New Jersey, 530 U.S. 466 (right to jury on facts increasing penalty)
Blakely v. Washington, 542 U.S. 296 (defendant may consent to judicial factfinding for enhancements)
Duncan v. Louisiana, 391 U.S. 145 (waiver of jury trial with intelligent consent)
United States v. Christensen, 18 F.3d 822 (written waiver and Rule 23/consent principles)
United States v. Shorty, 741 F.3d 961 (written waiver creates presumption of voluntariness)
United States v. Schrock, 855 F.2d 327 (identity of drugs may be proved circumstantially)
People v. Davis, 303 P.3d 1179 (naming a substance alone may be insufficient to prove composition)
United States v. Davis, 114 F.3d 400 (pretrial‑release enhancement applies despite acquittal of underlying charge)
United States v. Blake, 116 F.3d 1202 (chemical characterization of methamphetamine)
United States v. Dolan, 544 F.2d 1219 (judicial notice of drug identity admissible)