Sammy Tawakkol v. Sheila Vasquez, in Her Official Capacity as Manager of the Texas Department of Public Safety- Sex Offender Registration Bureau; And Freeman F. Martin, in His Official Capacity as Director of the Texas Department of Public Safety, 15-25-00009-CV

Sammy Tawakkol sought an injunction to prevent Texas officials from requiring him to register as a sex offender based on a prior conviction under the Uniform Code of Military Justice (UCMJ).
The federal district court granted an injunction, finding the Secretary of Defense lacked authority to designate his offense as a registrable sex offense.
On appeal, the Fifth Circuit vacated the injunction, holding that officials were enforcing a state law consistent with federal law and sovereign immunity barred the claims.
After failing to revive his federal case, Tawakkol filed the same claims in Texas state court, omitting federal constitutional arguments.
The state district court dismissed his claims for lack of jurisdiction, accepting defenses of res judicata, collateral estoppel, and no statutory cause of action; Tawakkol appealed.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Res Judicata (Claim Preclusion)	Federal vacatur didn't address merits of his claim, so res judicata doesn't apply	Same parties, claims, and a final federal judgment bar relitigation	Res judicata bars current suit
Collateral Estoppel (Issue Preclusion)	Previous litigation didn't fully or fairly decide this specific issue	Federal court already fully litigated and resolved the necessary issues	Collateral estoppel bars relitigation
Right to Challenge under Texas Law	Texas law (Art. 62.003) allows appeal of registration determination	Art. 62.003 inapplicable—Tawakkol is extrajurisdictional registrant, no appeal right	No Texas statutory cause of action
Ultra Vires/State Authority	State officials act beyond their authority by requiring registration	Officials enforce mandatory federal/state law; no ultra vires act	No ultra vires claim; no jurisdiction

Barr v. Resolution Trust Corp., 837 S.W.2d 627 (Tex. 1992) (outlines elements of res judicata in Texas law)
Citizens Ins. Co. of Am. v. Daccach, 217 S.W.3d 430 (Tex. 2007) (explains claim preclusion and privity)
Igal v. Brightstar Info. Tech. Group, 250 S.W.3d 78 (Tex. 2008) (clarifies finality and jurisdiction for res judicata)
Engelman Irrigation Dist. v. Shield Bros., 514 S.W.3d 746 (Tex. 2017) (holds sovereign immunity dismissal may have preclusive effects)
Sysco Food Servs., Inc. v. Trapnell, 890 S.W.2d 796 (Tex. 1994) (explains collateral estoppel/issue preclusion standard)
Johnson & Higgins of Tex., Inc. v. Kenneco Energy, Inc., 962 S.W.2d 507 (Tex. 1998) (articulates elements for issue preclusion)