The Chapter 64 motion framework
Texas Code of Criminal Procedure Articles 64.01-64.05 set out the motion procedure, eligibility standards, and post-results procedures for post-conviction DNA testing. The motion is filed in the convicting court, the State has an opportunity to respond, and the court rules on the motion before any testing is ordered.
- Art. 64.01 — Motion contents and counsel
- The motion must request DNA testing of biological material in the State's possession, identify the evidence sought to be tested, and explain the relevance to the case. The motion must be filed with the convicting court. The defendant may be represented by counsel — if indigent, the convicting court must appoint counsel to assist with the motion if the defendant has filed sufficient pro se papers and the court determines reasonable grounds exist for the motion. Art. 64.01(c) provides for appointment of counsel; in practice, well-prepared pro se motions improve the likelihood of counsel appointment significantly.
- Art. 64.03(a)(1) — Material requirements
- The court may order testing only if it finds biological material exists in a condition that makes DNA testing possible, that the material has been subjected to a chain of custody sufficient to establish that it has not been substituted, tampered with, replaced, or altered in any material respect, and that identity was or is an issue in the case. The chain-of-custody finding has been particularly important in DFW Conviction Integrity Unit reviews where evidence has been in storage for decades.
- Art. 64.03(a)(2) — Substantive standard
- The court must order testing if the defendant establishes by a preponderance of the evidence that he or she would not have been convicted if exculpatory results had been available at trial, AND that the request is not made to unreasonably delay the execution of sentence or the administration of justice. The "would not have been convicted" standard is interpreted as a reasonable-probability test — the defendant must show exculpatory results would have created a reasonable probability of acquittal. Routier v. State, 273 S.W.3d 241 (Tex. Crim. App. 2008), and Hooker v. State, 621 S.W.3d 320 (Tex. Crim. App. 2021), interpret this standard in detail.
- Art. 64.05 — Appellate review
- A defendant or the State may appeal a Chapter 64 ruling to the Court of Appeals — the courts of appeals have direct appellate jurisdiction over Chapter 64 orders. The appeal proceeds under Texas Rule of Appellate Procedure 25 with standard appellate timelines. A discretionary review petition to the Court of Criminal Appeals is available. Chapter 64 appeals are heard regularly in the Fifth District Court of Appeals (Dallas) covering Collin, Dallas, and adjacent counties, and the Second District Court of Appeals (Fort Worth) covering Tarrant and adjacent counties.
The Chapter 64 motion is the statutory vehicle for accessing post-conviction DNA testing in Texas. The motion is not itself an innocence claim — it is a discovery-and-testing-access vehicle whose results may then support a separate habeas application under Article 11.07 or Article 11.073. The defendant who obtains favorable DNA test results files a habeas petition seeking actual-innocence relief and may also pursue parallel federal § 1983 access claims under Skinner v. Switzer. Successful Chapter 64 motions therefore initiate a multi-step process that can take years from initial filing to exoneration.
The motion procedure is comparatively informal. The defendant files the motion (pro se or with counsel) identifying the evidence sought to be tested. The State responds — typically requiring substantial time to retrieve and inventory the biological material from law-enforcement storage. The convicting court rules on the motion after considering the parties' filings; an evidentiary hearing is held in some cases but is not required by statute. A grant order specifies the evidence to be tested and the laboratory protocol. The Texas Department of Public Safety crime laboratory and accredited private laboratories perform the testing under court-supervised protocols.
The motion can be filed at any time during the period of conviction — there is no statute of limitations under Chapter 64. The defendant may file multiple motions if new technology becomes available or new evidence is identified. Hooker v. State, 621 S.W.3d 320 (Tex. Crim. App. 2021), clarified that the diligence analysis operates within the merits review rather than as a procedural bar. A defendant whose first motion is denied is not necessarily barred from later motions if changed circumstances support reconsideration.
The reasonable probability analysis under Art. 64.03(a)(2)
The "would not have been convicted" standard requires more than a possibility of a different outcome — the defendant must show a reasonable probability that exculpatory DNA results would have produced acquittal. The trial court considers the strength of the existing evidence, the centrality of identity to the conviction, and the likely impact of exculpatory results in context.
Article 64.03(a)(2)(A) requires the trial court to order testing if the defendant establishes by a preponderance of the evidence that "the person would not have been convicted if exculpatory results had been obtained through DNA testing." The Texas Court of Criminal Appeals has interpreted "would not have been convicted" as requiring a reasonable-probability showing — the defendant must demonstrate that exculpatory results would have created a reasonable probability of a different outcome at trial, not merely a possibility. Routier v. State, 273 S.W.3d 241 (Tex. Crim. App. 2008), articulated this standard, and subsequent decisions have refined the analysis.
The reasonable-probability analysis is contextual. The trial court considers the existing trial record in its entirety — the strength of identification evidence other than the proposed DNA testing, the role of forensic evidence in the conviction, the centrality of identity to the prosecution's case, and the likely effect of exculpatory results on the jury's reasoning. Where the prosecution's case rested heavily on contested eyewitness identification and the proposed DNA testing addresses the identity of the perpetrator, the reasonable-probability showing is comparatively straightforward. Where the prosecution's case rested on multiple independent grounds of guilt — confession, extensive circumstantial evidence, multiple eyewitnesses — the reasonable-probability showing is more difficult.
The defendant need not show actual innocence to prevail under Chapter 64. The standard is comparative — would the exculpatory result have changed the trial outcome — rather than absolute. Even a defendant whose guilt is not seriously contested may obtain testing if the testing addresses a discrete identity-related issue (e.g., whether a third party's biological material was present at the scene). The post-testing path requires more — actual innocence under Article 11.07 or 11.073 requires a stronger showing — but the initial Chapter 64 grant requires only the reasonable-probability showing.
Practical strategy for the reasonable-probability showing focuses on developing the evidentiary record on (1) the centrality of identity to the conviction; (2) the absence or weakness of non-DNA identification evidence; (3) the likely jury reaction to exculpatory results in the context of the prosecution's case; and (4) the technological advances that make new testing capable of producing more probative results than any prior testing. Expert affidavits on the third-party transfer of biological evidence, the discriminatory power of modern STR and Y-STR testing, and the limitations of pre-PCR forensic techniques are standard components of well-prepared Chapter 64 motions.
Biological-material preservation under Art. 38.43
Texas Code of Criminal Procedure Article 38.43 requires the State to preserve biological material in its possession during the period of conviction. The preservation duty applies to evidence in custody of any agent of the State; failure to preserve can support both an Art. 64 motion and a separate due-process claim.
Texas Code of Criminal Procedure Article 38.43 sets out the State's biological-material preservation obligations. The statute requires the State to preserve biological material in its possession during the period of conviction — generally meaning until the conviction has been fully served or the sentence has been completed. The preservation duty applies broadly to biological evidence held by law enforcement, prosecution, crime laboratories, court clerks, and any agent of the State. Specific exceptions exist for evidence consumed by testing, evidence returned to a rightful owner under defined procedures, and biological samples that have degraded beyond usability.
The preservation duty has been refined through Texas legislative amendments over the past two decades. The 2007 and 2011 amendments expanded the scope of evidence subject to preservation and tightened the procedures required before destruction. The 2015 amendments addressed evidence in cases without a known suspect at the time of evidence collection — biological evidence in such cases must be preserved indefinitely or until a conviction is fully served. The cumulative effect is a robust preservation framework that supports later Chapter 64 motions even decades after the underlying conviction.
Failure to preserve biological material can produce several legal consequences. First, the failure can support a Chapter 64 motion based on the State's lack of explanation for missing evidence — the trial court may presume the missing evidence was relevant and probative. Second, the failure can support a separate due-process claim under Arizona v. Youngblood, 488 U.S. 51 (1988), if the State acted in bad faith in destroying the evidence. California v. Trombetta, 467 U.S. 479 (1984), addressed similar preservation obligations in the pretrial context. Third, the failure can support relief under the Texas constitutional due-course-of-law guarantee under Tex. Const. art. I, § 19, which has been interpreted to provide broader protection than the federal Due Process Clause in some preservation contexts.
Practical Chapter 64 work begins with a State-response review of biological evidence inventory. The defendant's motion identifies the evidence sought to be tested; the State's response must address whether the evidence exists, where it is stored, and whether the chain of custody is sufficient. Many Chapter 64 motions have been resolved at this preliminary stage — either by State agreement to test (where the evidence is intact and the political will to support testing exists) or by State inability to locate the evidence (which then supports either a default order in the defendant's favor or a separate Trombetta/Youngblood claim). Counsel should expect a State-response timeline of 60-120 days from motion filing.
Federal access right — Skinner v. Switzer
Skinner v. Switzer, 562 U.S. 521 (2011), held that a state prisoner may bring a 42 U.S.C. § 1983 action for federal-court access to DNA testing of biological evidence in the State's possession. The federal pathway operates parallel to Texas Chapter 64 and provides a venue for testing access where state remedies are unconstitutionally inadequate as applied.
Skinner v. Switzer, 562 U.S. 521 (2011), addressed a Texas death-row prisoner's § 1983 claim for access to DNA testing of biological evidence after exhausting Texas state-court remedies. Justice Ginsburg's majority opinion held that the § 1983 procedural-due-process claim was the proper vehicle for the access claim — distinguishing it from Heck v. Humphrey, 512 U.S. 477 (1994), which bars § 1983 claims that necessarily imply invalidity of an underlying conviction. The Court held that an access-to-testing claim does not necessarily imply invalidity because the test results might confirm guilt rather than support innocence.
The Skinner decision did not establish a substantive federal due-process right to DNA testing. That question had been resolved by District Attorney's Office v. Osborne, 557 U.S. 52 (2009), which held that no such substantive right exists — the right to post-conviction DNA testing is governed by state-law procedural frameworks. Skinner addressed only the procedural question of whether § 1983 was an available vehicle when state remedies were exhausted and the state procedure had been applied in a way the prisoner alleged was unconstitutional. The federal court can review only the state procedural framework as applied, not the merits of whether testing should be granted.
In practice, the federal § 1983 pathway under Skinner has been used in Texas in cases where the state Chapter 64 procedure was applied in a manner the defendant alleges violated procedural due process. Common contexts include (1) trial-court refusal to consider chain-of-custody evidence the defendant offered to develop; (2) State refusal to produce biological evidence inventory or status information; (3) trial-court application of incorrect substantive standards under Art. 64.03(a)(2); and (4) appellate-court refusal to review the trial-court ruling under standard appellate procedure. The federal § 1983 action seeks an order directing the State to permit testing — not a substantive innocence ruling.
The strategic interaction of Chapter 64 motions and § 1983 access actions has been refined since Skinner. Defense counsel typically pursue Chapter 64 motions first in the convicting court, exhausting state-court remedies before considering federal § 1983 action. The § 1983 action is reserved for cases where the state procedure has been applied unconstitutionally as applied — not as a substitute for state Chapter 64 motion practice. The remedy in a successful § 1983 action is an order directing the State to permit testing; the actual testing occurs in state-court-supervised procedures after the federal court ruling.
Integration with Article 11.073 — the junk-science writ
Texas's 2013 Article 11.073 provides actual-innocence relief based on scientific evidence that has been discredited, superseded, or substantially undermined. Where Chapter 64 DNA testing produces results that contradict the original forensic narrative, Article 11.073 is the typical post-testing relief vehicle.
Texas Code of Criminal Procedure Article 11.073 — the first state "junk-science writ" enacted in 2013 — addresses post-conviction relief for convictions based on scientific evidence later discredited, superseded, or substantially undermined. The writ requires the defendant to show (a) relevant scientific evidence that was not available at the time of trial OR contradicts scientific evidence relied on by the State at trial; AND (b) the new scientific evidence would more likely than not result in acquittal if it had been presented. Article 11.073 was enacted specifically to address forensic-science errors including arson-investigation, bite-mark, hair-microscopy, bullet-lead-analysis, and other discredited or refined forensic methods.
The interaction between Chapter 64 DNA testing and Article 11.073 is structural. A defendant who obtains favorable DNA testing under Chapter 64 typically files a parallel or subsequent Article 11.073 application based on the new DNA evidence — particularly where the trial featured DNA evidence (or comparable forensic evidence) that the new testing contradicts. The Article 11.073 application addresses substantive innocence; the Chapter 64 motion addresses only access to testing. The two motions can be filed sequentially or in parallel, depending on the strategic posture and the state of the underlying evidence.
Article 11.073 has produced documented exonerations across Texas. The Innocence Project of Texas has supported successful Article 11.073 applications in cases involving discredited bite-mark testimony, faulty hair-microscopy comparisons, arson-investigation errors based on outdated fire-pattern analysis, and bullet-lead-analysis results later shown to lack scientific validity. The Dallas County District Attorney's Conviction Integrity Unit — one of the most active in the United States — has supported Article 11.073 applications in cooperative review of long-completed convictions where forensic-science problems became apparent.
The "more likely than not" standard under Article 11.073(a)(2) is a higher threshold than the Chapter 64 reasonable-probability standard. The defendant must show that the new scientific evidence — including DNA testing results — would more likely than not have produced acquittal at trial. The court considers the totality of the trial record and the impact of the new evidence in that context. Successful Article 11.073 applications produce reversal of the conviction and remand for new trial or, in many cases, dismissal of the prosecution where the State concludes prosecution is no longer viable.
Strategic coordination between Chapter 64 and Article 11.073 work is essential. The Chapter 64 motion focuses on access — getting the testing done. The Article 11.073 application focuses on substantive innocence — what the testing results mean. A well-prepared Chapter 64 motion anticipates the eventual Article 11.073 application and develops the evidentiary record (chain of custody, technological advances, comparative likelihood of trial-outcome change) that will support the later substantive innocence claim. Defense counsel often work in coordinated teams — Chapter 64 counsel handles motion-procedure work, while habeas counsel handles the Article 11.073 substantive innocence claim.
DFW court patterns — Conviction Integrity Units and Innocence Project work
Dallas County operates one of the most active Conviction Integrity Units in the United States, supporting Chapter 64 and Article 11.073 work. Tarrant, Collin, and Denton counties also handle post-conviction DNA testing through their district-court systems and DA conviction-review processes.
The Dallas County District Attorney's Office Conviction Integrity Unit was established in 2007 and remains one of the most institutionalized CIU operations in the United States. The unit reviews post-conviction innocence claims, supports Chapter 64 motion practice, and has cooperated in dozens of exonerations through Chapter 64 and Article 11.073 proceedings. The CIU's active engagement with Innocence Project of Texas and the National Registry of Exonerations has made Dallas County one of the leading jurisdictions for post-conviction innocence work nationally. Defense counsel filing Chapter 64 motions in Dallas County typically engage with CIU staff to assess State posture before formal motion filing.
Tarrant County has a more recent but increasingly active Conviction Integrity Unit operating out of the Criminal District Attorney's office. The Tarrant CIU has supported Chapter 64 and Article 11.073 work and has cooperated in exoneration proceedings on cases involving forensic-science errors and DNA-based identification issues. The Tim Curry Criminal Justice Center handles the bulk of Tarrant felony post-conviction work, including Chapter 64 motions. Practitioners in Tarrant should engage with CIU staff and the felony courts' post-conviction track early in any Chapter 64 motion.
Collin County does not operate a formal Conviction Integrity Unit but handles Chapter 64 motions through the District Attorney's office and the McKinney district-court system. Chapter 64 motions in Collin proceed through standard motion practice without dedicated CIU review. Practitioners should anticipate longer timelines for State responses where the evidence is in older storage, and should develop the chain-of-custody and biological-material-inventory record before motion filing.
Denton County similarly handles Chapter 64 work through the District Attorney's office and the felony courts without a dedicated CIU. The Denton DA has cooperated in selected Chapter 64 motions where the underlying evidence supported reasonable testing requests. Practitioners filing Chapter 64 motions in Denton coordinate with the DA's felony chief and the assigned felony court to develop the motion record. The Denton County district-court Chapter 64 docket is smaller than Dallas or Tarrant, but each motion receives substantial individual attention.
The Innocence Project of Texas — operating across the state from law-school clinics at the University of Texas at Tyler and Texas A&M University School of Law — provides representation and consultation in Chapter 64 and Article 11.073 cases statewide. The project has supported documented exonerations across DFW counties and operates a screening process for cases meeting Chapter 64 and Article 11.073 criteria. Defense counsel handling Chapter 64 work should consider Innocence Project consultation for complex cases involving extensive forensic-science contests or multi-defendant testing access.
Practical motion development — what to include in a Chapter 64 motion
A well-prepared Chapter 64 motion includes a detailed inventory of the biological evidence sought, a chain-of-custody analysis, expert affidavits on testing methodology and likely results, and an evidentiary showing on the reasonable-probability standard. Motions developed with these components have substantially higher grant rates than skeleton pro se filings.
A Chapter 64 motion that succeeds requires several distinct evidentiary components. First, an inventory and identification of the biological evidence sought to be tested — referencing specific items by trial-exhibit number, lab-case number, or property-room item number where available. The motion should identify the specific physical location of each item if known and request the State to confirm location and chain of custody. Second, an analysis of why DNA testing of the identified items would produce probative results — typically requiring expert affidavit on the type of biological material, the likelihood of preservable DNA, and the discriminatory power of available testing methodologies (autosomal STR, Y-STR, mitochondrial, SNP, or next-generation sequencing where appropriate).
Third, a chain-of-custody analysis. The motion must address whether the biological evidence has been subjected to a chain of custody sufficient to establish that it has not been substituted, tampered with, replaced, or altered in any material respect under Art. 64.03(a)(1)(A)(ii). The motion should attach trial-record citations, evidence-log documentation, and any other support for the chain of custody. Defects in the chain of custody can defeat a Chapter 64 motion entirely — even where the underlying biological material is otherwise testable.
Fourth, an evidentiary showing on the reasonable-probability standard under Art. 64.03(a)(2). The motion must demonstrate that exculpatory test results would have created a reasonable probability of acquittal. This typically requires (a) a trial-record summary identifying the centrality of identity to the conviction; (b) analysis of the non-DNA identification evidence (eyewitness identification, confession, other forensic evidence) and its strength or weakness; (c) expert affidavit on the likely jury reaction to exculpatory DNA evidence in the context of the existing trial record; and (d) where applicable, comparative analysis showing how technological advances since the original trial would produce more probative testing than was previously available.
Fifth, procedural compliance. The motion must be filed in the convicting court; must request appointment of counsel under Art. 64.01(c) if the defendant is indigent and the motion meets statutory criteria; must serve the State and any other interested parties; and must include the statutory verifications and certifications. Pro se motions that omit procedural requirements are routinely denied without prejudice; refiling adds substantial delay. Defense counsel who handle Chapter 64 motions regularly maintain template language and procedural checklists to ensure compliance.
Sixth, anticipation of the post-testing phase. A well-prepared Chapter 64 motion contemplates the eventual Article 11.073 application or other substantive innocence claim that exculpatory testing would support. The motion should preserve issues for later use and develop record components — for example, by including affidavits or expert analysis that will be relevant to the eventual habeas application. Coordination between Chapter 64 counsel and habeas counsel during motion preparation produces a stronger record than sequential preparation by different teams.
