Pena, Martin, WR-84,073-01

Applicant Martin Pena pleaded guilty to possession with intent to deliver cocaine (400+ grams) and received a 15‑year sentence; he later filed a habeas application raising two claims.
Arresting Officer Carrion allegedly was involved with a drug cartel, stole the cartel’s cocaine, and replaced it with an ice chest of sheetrock sprinkled with less than one gram of cocaine. Carrion participated in the traffic stop and seizure.
Prosecutors did not disclose Carrion’s misconduct to Pena before plea; the State concedes Carrion’s misconduct is imputed to the prosecution for Brady purposes.
Pena’s habeas claims: (1) Brady violation for failure to disclose exculpatory/impeachment evidence; (2) plea involuntary/not knowing because material facts (Carrion’s conduct and the tiny cocaine amount) were undisclosed.
The dissenting justice (Walker, joined by Alcala and Richardson) concludes the suppressed evidence was both impeaching and truly exculpatory and that Pena was prejudiced, so relief should be granted under either claim.

Issue	Pena's Argument	State's Argument	Held
Brady suppression of evidence of Officer Carrion’s misconduct	Carrion’s conduct (working for cartel, stealing cocaine, replacing it with sheetrock with only trace cocaine) was favorable, material, and suppressed by the State; nondisclosure undermined confidence in the conviction	Evidence is impeachment and not required to be disclosed before a plea (relying on Ruiz and majority view)	Dissent: Evidence was both impeaching and actually/exactly exculpatory; suppression was imputed to prosecution and produced a reasonable probability of a different result — Brady violation warranting relief
Involuntary/unknowing plea due to nondisclosure of Carrion’s misconduct and the true cocaine quantity	Pena would not have accepted the 15‑year plea if he’d known Carrion’s role and that the substance likely contained <1 gram; materiality of undisclosed facts made plea unknowing and involuntary	State contends plea was valid; majority rejects voluntariness claim	Dissent: The undisclosed facts were material to Pena’s choice; a reasonable defendant/attorney would have rejected the plea — plea was not knowing/voluntary; relief warranted

Brady v. Maryland, 373 U.S. 83 (1963) (prosecution must disclose favorable evidence material to guilt or punishment)
United States v. Bagley, 473 U.S. 667 (1985) (Brady duty includes impeachment evidence)
United States v. Ruiz, 536 U.S. 622 (2002) (impeachment evidence need not always be disclosed before a guilty plea)
Youngblood v. West Virginia, 547 U.S. 867 (2006) (Brady suppression may occur where evidence is known only to police)
Strickler v. Greene, 527 U.S. 263 (1999) (three components of Brady: favorable, suppressed, material/prejudicial)
Kyles v. Whitley, 514 U.S. 419 (1995) (materiality standard and prosecutor’s duty to learn of favorable evidence known to others)
Ex parte Castellano, 863 S.W.2d 476 (Tex. Crim. App. 1993) (officer acting under color of law whose fabrication knowledge is imputable to prosecution)
Jose Luis Pena v. State, 353 S.W.3d 797 (Tex. Crim. App. 2011) (distinguishing exculpatory and impeachment evidence)
Seals v. State, 187 S.W.3d 417 (Tex. Crim. App. 2005) (adulterant/dilutant aggregation analysis)
Ex parte Mable, 443 S.W.3d 129 (Tex. Crim. App. 2014) (plea must be knowing and voluntary with sufficient awareness of relevant circumstances)
Ex parte Barnaby, 475 S.W.3d 316 (Tex. Crim. App. 2015) (materiality in plea context measured by effect on defendant’s decision to plead)