Concrete Evidence Requirement in Establishing Prejudice for Ineffective Assistance of Counsel on Federal Habeas Review

Introduction

Caballero v. Miller is a Second Circuit summary order reversing a district‐court grant of habeas relief under 28 U.S.C. § 2254. Petitioner‐appellee Andrew Caballero was convicted in New York state court for a brutal 1995 rooftop killing. He claimed on federal habeas that his trial counsel (Robert DiDio) failed to investigate key witnesses and an alternative suspect (Michael Lugo), and that his appellate counsel (Danielle Muscatello) failed to raise that deficiency on direct appeal. The district court granted relief, finding both performance and prejudice under Strickland v. Washington. The Second Circuit reversed, holding that without a proffer of what additional investigation would have revealed, a petitioner cannot establish the necessary prejudice, and that appellate‐counsel claims dependent on trial‐counsel failures likewise fail.

Summary of the Judgment

• The State appealed after the Eastern District of New York granted Caballero a writ of habeas corpus, concluding trial counsel was ineffective for failing to investigate impeaching witnesses and an alternative suspect, and that appellate counsel was ineffective for not raising that claim on direct appeal.
• The Second Circuit applied the twin deferential standards of AEDPA (“doubly deferential” review) and Strickland.
• On trial‐counsel claims, the court held Caballero had not shown prejudice because he failed to present evidence about what the putative witnesses would have said or whether they would testify.
• On appellate‐counsel claims, the court held that under New York law such ineffectiveness claims belong in collateral proceedings, and in any event Caballero could not show a reasonable probability of success on appeal absent a showing of prejudice.
• The court therefore reversed the grant of habeas relief.

Analysis

Precedents Cited

Strickland v. Washington, 466 U.S. 668 (1984): Sets the two‐pronged test for ineffective assistance—deficient performance and prejudice.
28 U.S.C. § 2254(d) (AEDPA): Habeas relief is available only if a state‐court decision is contrary to or an unreasonable application of clearly established federal law.
Harrington v. Richter, 562 U.S. 86 (2011): Emphasizes the “doubly deferential” standard when AEDPA and Strickland overlap.
Clark v. Perez, 510 F.3d 382 (2d Cir. 2008): Habeas‐review standards for fact‐finding and legal questions.
Lindstadt v. Keane, 239 F.3d 191 (2d Cir. 2001): Counsel’s failure to interview key witnesses clearly prejudiced the defense, because proffered testimony would have undercut the prosecution’s theory.
Schulz v. Marshal, 345 F. App’x 627 (2d Cir. 2009): Similar to Lindstadt, showing prejudice where un‐interviewed eyewitness would have exculpated the defendant.
Pierotti v. Walsh, 834 F.3d 171 (2d Cir. 2016): Under New York law, ineffective‐assistance claims relying on facts outside the trial record must be brought in collateral proceedings, not on direct appeal.

Legal Reasoning

1. Standard of Review
The court reviews grants or denials of habeas relief de novo, but state‐court findings for clear error (Clark) and state‐court legal conclusions under § 2254(d) for an unreasonable application of federal law (Harrington). Ineffective‐assistance claims require showing both deficient performance and prejudice (Strickland).

2. Trial Counsel
Caballero alleged DiDio failed to investigate (a) alternative suspect Michael Lugo and (b) potential impeachment of the prosecution’s key witnesses, Oscar Balarezo and Nadia Sierra, based on late‐disclosed Rosario materials. Under Strickland, prejudice requires a “reasonable probability” of a different result. Unlike Lindstadt or Schulz, Caballero offered no affidavits or witness testimony to show what the additional investigation would have uncovered. Without a concrete proffer of exculpatory or impeaching evidence, the state court reasonably concluded there was no showing of prejudice.

3. Appellate Counsel
Caballero argued that Muscatello should have raised the trial‐counsel‐investigation claim on direct appeal. New York practice requires that fact‐intensive ineffective‐assistance claims be litigated in collateral (440.10) proceedings (Pierotti). Even if the claim could have been raised on direct appeal, Caballero could not show a reasonable probability that New York’s highest court would have found prejudice without the same factual showing he failed to make in state collateral proceedings.

Impact

• This decision underscores that on federal habeas review a petitioner relying on ineffective assistance for failure to investigate must present, in the state‐court record or by proffer, specific evidence of what testimony or evidence would have been uncovered.
• The ruling reinforces the “doubly deferential” standard when AEDPA and Strickland overlap: a state court’s resolution of an ineffective‐assistance claim will stand unless it is objectively unreasonable.
• Criminal defense lawyers should document potential leads and anticipated evidence when deciding not to pursue certain lines of investigation, to preclude later claims of deficient performance.
• Appellate practitioners in New York should raise only record‐based ineffective‐assistance claims on direct appeal, deferring fact‐driven claims to collateral proceedings.

Complex Concepts Simplified

AEDPA Deference: Federal courts may overturn a state‐court decision only if it is not just wrong, but unreasonably so under clearly established Supreme Court precedent.
Strickland Two‐Pronged Test: (1) Counsel’s performance must fall below an objective standard of reasonableness. (2) There must be a “reasonable probability” that, but for counsel’s errors, the outcome would have been different.
Rosario Doctrine: Under New York law, prosecutors must disclose prior statements of witnesses so defense can use them to impeach credibility.
Coram Nobis: A post‐conviction remedy in New York to correct errors of fact or law not addressed on direct appeal.

Conclusion

Caballero v. Miller clarifies that in ineffective‐assistance claims based on alleged failures to investigate, a habeas petitioner must show concrete prejudice by proffering what evidence a proper investigation would have revealed. Absent that evidentiary showing, neither trial counsel’s performance nor appellate counsel’s failure to raise the issue on direct appeal can satisfy Strickland’s prejudice prong. The decision reaffirms the high hurdle petitioners face on federal habeas review under AEDPA and underscores the importance of thorough pretrial investigation and clear trial‐record documentation for defense counsel.