State of Tennessee v. Mario Cruz Estrada, M2016-00056-CCA-R3-CD

Defendant Mario Cruz Estrada was convicted of attempted second-degree murder and sentenced to 12 years in confinement after stabbing victim Charles Davis during an altercation at the Davis home.
Prior to the stabbing, an intoxicated girlfriend of the defendant (Crystal Carranza) and the defendant arrived with the girlfriend’s young child; a confrontation ensued in the bathroom in which Carranza hit Davis and Davis subdued her.
While Davis was restraining Carranza on the floor, the defendant allegedly stabbed Davis repeatedly; Davis was rendered unconscious and later hospitalized; defendant fled in a minivan but was apprehended shortly after, wearing bloodstained clothing.
Deputies photographed the defendant at arrest, collected his bloody clothing in a sealed paper bag, and that clothing was later tested by the TBI; DNA on the clothes and in the van matched the victim.
At trial the defendant requested jury instructions on self-defense and defense of another; the trial court denied those instructions and admitted the clothing and DNA evidence over a chain-of-custody challenge.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether the trial court erred by refusing to instruct the jury on self-defense and defense of another	State: Evidence did not fairly raise self-defense/defense of another; no reasonable belief of imminent deadly or serious harm	Estrada: He reasonably believed Carranza was in imminent danger of serious bodily injury and acted to defend her (and himself)	Court affirmed: No instruction required because evidence did not show a real or reasonable belief of imminent death or serious bodily injury
Whether the trial court abused its discretion by admitting the defendant’s bloody clothing and resulting DNA analysis due to an inadequate chain of custody	State: Chain of custody sufficiently established identity and integrity of the clothing; gaps go to weight, not admissibility	Estrada: The State failed to prove an unbroken chain; possible tampering or substitution made evidence unreliable	Court affirmed: Proof was sufficient to reasonably assure no substantial alteration; any imperfections were for the jury to consider

State v. Harbison, 704 S.W.2d 314 (Tenn. 1986) (trial court must give complete charge of law applicable to facts)
State v. Sims, 45 S.W.3d 1 (Tenn. 2001) (defense instruction warranted only if evidence, viewed in defendant's favor, could reasonably support it)
State v. Scott, 33 S.W.3d 746 (Tenn. 2000) (Rule 901 does not require proof beyond all doubt; admissibility turns on reasonable assurance of identity/integrity)
State v. Johnson, 673 S.W.2d 877 (Tenn. Crim. App. 1984) (even with chain gaps, tangible evidence may be admitted if trial judge finds no substantial alteration)