Background
Stephen DeRossett was convicted of second-degree murder in the January 1, 2020 stabbing death of his girlfriend, Keli Jackson. DeRossett called 911 reporting that Jackson had been drinking, came at him aggressively, and he pushed her down the stairs. When paramedics arrived, Jackson lay in a pool of blood, unconscious and unresponsive. She was pronounced dead at the scene. The autopsy revealed 15 stab wounds, four of which were lethal, and death resulted from blood loss. A knife with DeRossett’s name engraved on it was found nearby with blood on it.
DeRossett had scratches on his face and body, and toxicology showed a blood alcohol level of 0.116 and THC in his system. The trial lasted multiple days, during which DeRossett offered two defenses: (1) he acted in self-defense, and (2) he lacked the requisite mental state for murder due to intoxication and lasting effects of a prior traumatic brain injury from a motorcycle accident decades earlier requiring emergency brain surgery. The jury acquitted him of first-degree murder but convicted him of second-degree murder and two crime of violence enhancements, resulting in a 40-year sentence.
The Court’s Holding
The Colorado Court of Appeals affirmed DeRossett’s conviction on all counts. Although the court found that the trial court abused its discretion by admitting 33 autopsy photographs that were often cumulative and unnecessary, it held the error was harmless and did not require reversal. The court noted the photographs were highly probative of the primary disputed issues—DeRossett’s mental state at the time and whether his response constituted self-defense—particularly whether stabbing the victim 15 times was a reasonable response to the threat he faced. Most photographs offered different perspectives (close-ups, different angles, with measuring tools), and each was discussed during the forensic pathologist’s testimony. Critically, the evidence of guilt was overwhelming: DeRossett admitted killing Jackson, the autopsy established 15 stab wounds with four being lethal, and DeRossett provided inconsistent statements about how the wounds occurred.
The court also rejected DeRossett’s challenges to the prosecution’s expert testimony and jury instructions. It held that a prosecution psychologist’s diagnosis of severe alcohol use disorder and an unspecified personality disorder (with narcissistic, antisocial, and borderline traits) was properly admitted to rebut DeRossett’s mental condition evidence. The court concluded these rulings, even if erroneous in part, did not affect the fairness of the trial given the strength of the prosecution’s case and the jury’s careful deliberation (evidenced by its conviction on the lesser offense of second-degree rather than first-degree murder).
Key Takeaways
- Autopsy photographs may be admitted in substantial numbers even if cumulative when they are probative of disputed material issues such as mental state and self-defense, provided the prosecution’s overall evidence of guilt is overwhelming.
- Photographs showing different angles, close-ups, and scales constitute admissible variations rather than purely cumulative exhibits, and courts have discretion to weigh probative value against inflammatory effect under Colorado Rules of Evidence 403.
- Expert testimony diagnosing personality disorder traits may be admissible to rebut defense evidence of mental condition when the defendant has placed that issue before the jury through opening statements and cross-examination of prosecution witnesses.
- A defendant cannot stipulate his way out of the full evidentiary force of the prosecution’s case; the prosecution retains broad discretion in selecting the evidence through which to prove its case.
Why It Matters
This decision provides critical guidance for trial courts navigating the tension between probative value and inflammatory effect in violent crime cases. While the opinion acknowledges that cumulative graphic photographs may constitute an abuse of discretion, it establishes a high bar for reversal when the prosecution’s evidence is strong and the central disputed issues (mental state and self-defense) are directly implicated. For defense counsel, the decision underscores the difficulty of challenging voluminous visual evidence even when portions are redundant or designed to inflame the jury’s emotions—harmless error doctrine protects convictions supported by overwhelming corroborating evidence.
The ruling also clarifies the scope of expert rebuttal testimony in mental condition cases. By admitting evidence of personality disorders to counter the defense’s brain injury theory, the court permits prosecutors to challenge mental state defenses through character evidence presented by qualified experts. This has significant implications for defendants raising cognitive or emotional impairment arguments, as prosecutors can now introduce competing psychological diagnoses without triggering statutory restrictions on evidence from court-ordered mental health evaluations.