State v. Mendoza, 1 CA-CR 23-0409

In December 2001, police discovered Robert (pseudonym), deceased with signs of strangulation and sexual activity, in his home; DNA and fingerprints from the scene did not match any known profiles, and the case went cold.
In 2018, advancements in technology linked fingerprints and partial familial DNA from the scene to Frank Gallas Mendoza's close male relative (his son), making Mendoza a suspect.
Law enforcement used GPS tracking and a California traffic stop to covertly obtain a DNA sample from Mendoza via a breathalyzer tube, for which they later obtained a search warrant.
Mendoza was arrested after a grand jury indictment that relied on fingerprint and familial DNA evidence (but not the California-derived DNA), and his buccal swab post-arrest matched DNA from the crime scene.
At trial, Mendoza challenged the admissibility of the DNA obtained in California and sought to disqualify all Maricopa County judges due to Judge Wahlin’s prior involvement as a witness and later as a presiding judge.
The trial court denied Mendoza’s suppression motions and motion to disqualify all judges; Mendoza was convicted and sentenced to natural life, then appealed.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Disqualification of all Maricopa County Judges	All judges should be disqualified due to appearance of impropriety (Judge Wahlin as witness)	No other judges personally involved; no evidence of partiality or prejudice	Motion properly denied; no reversible error or prejudice shown
Suppression of DNA from CA DUI investigation	DNA evidence was result of an unlawful search; should be suppressed as fruit of poisonous tree	Evidence from DUI was not presented to grand jury or used at trial; independent source	No error; DNA used at trial was obtained independently
Lawfulness of DUI stop/search of PBT tube	DUI stop and search lacked reasonable suspicion and warrant; search unlawful	Officers obtained a warrant for the breath tube; Mendoza abandoned privacy interest	Even assuming error, any issue was harmless—independent source
Admissibility of buccal swab DNA evidence	Buccal swab DNA was tainted by poisonous tree from CA stop	Swab obtained after grand jury indictment, not based on California DNA evidence	DNA evidence admitted; arrest and buccal swab not tainted

State v. Perkins, 141 Ariz. 278 (Ariz. 1984) (standard for reviewing judicial disqualification)
State v. Salazar, 182 Ariz. 604 (App. 1995) (relevant to judicial impartiality and disqualification)
State v. Menard, 135 Ariz. 385 (App. 1982) (presumption of trial court impartiality)
Terry v. Ohio, 392 U.S. 1 (1968) (Fourth Amendment, stop and frisk)