State v. Bivings

IN THE SUPERIOR COURT OF THE STATE OF DELAWARE

THE STATE OF DELAWARE )
)
Plaintiff, )
)
v. )
) Case No.: 2302002541
DERRICK BIVINGS )
)
Defendant. )

Submitted: April 3, 2025
Decided: July 3, 2025

Memorandum Opinion

Upon consideration of the State’s Motion to Exclude Expert
GRANTED in part and DENIED in part.

Diana A. Dunn, Esquire, Deputy Attorney General of DEPARTMENT OF JUSTICE,
Wilmington, Delaware 19801, Attorney for the State.

James M. Stiller, Jr. Esquire of SCHWARTZ & SCHWARTZ, P.A., Dover, Delaware
19901, Attorney for Defendant.

SCOTT, J.
The defendant stands accused of Rape Fourth Degree. In his defense, he seeks

to introduce expert testimony suggesting he suffers from sexsomnia, a form of

parasomnia, and the alleged conduct occurred during a sleep episode over which he

had no conscious awareness or control. The State moves to exclude the expert

witness. For the reasons stated herein, the motion is GRANTED in part and

DENIED in part.

BACKGROUND

On June 5, 2023, Derrick Bivings (“Defendant”) was indicted for Rape Fourth

Degree, and Sexual Abuse of a Person in a Position of Trust, Authority, or

Supervision First Degree of his then-sixteen-year-old niece A.H.M.

On July 12, 2024, Defendant submitted a report from Dr. Brian Angsten—an

expert in sleep medicine. The impressions provided were: sexsomnia and

sleepwalking/NREM parasomnia, obstructive sleep apnea, and insomnia. The

report, however, did not specify whether medical records and police reports were

reviewed, nor did it provide a conclusive opinion. Defendant indicated they intended

to call Dr. Angsten as an expert, with a supplemental report forthcoming.

In September 2024, Defendant provided the State with a sleep study

interpretation conducted by Masood Siddiqui, the supplemental report from Dr.
Angsten, and a report from Nurse Practitioner Demi Ogunwusi. Defendant indicated

they also intended to call Dr. Ogunwusi as an expert.

In November 2024, Defendant provided the State with the medical reports

reviewed by Dr. Angsten.

The Court held a conference on November 22, 2024. The State expressed

concerns “regarding the lack of substance contained in the expert reports provided,

the lack of nexus between the opinions rendered and the facts of the case, and the

reports or literature relied upon by the experts in rendering their opinions.”1

On November 25, 2024, Defendant submitted a more detailed report from Dr.

Angsten. But that report did not confirm whether any police reports or recorded

statements related to the incident were reviewed. Nor did it opine on whether

Defendant was experiencing sexsomnia during the incident.

On November 27, 2024, the State moved to exclude both Dr. Angsten and Dr.

Ogunwusi’s reports. Defendant opposed. The Court held a hearing addressing the

motion on December 4, 2024.

On March 5, 2025, Defendant filed a letter, as well as Dr. Angsten’s

addendum report dated February 3, 2025.2 The letter stated they intended to call

1
State’s First Motion to Exclude, D.I. 72.
2
D.I. 84.
Defendant’s wife and former girlfriend to testify about their personal observations

of his past abnormal sleep behaviors.3

The State renewed its motion on April 3, 2025 (the “Motion”).4 The matter is

now ripe for decision.

STANDARD OF REVIEW

The Court serves as a gatekeeper regarding the admissibility of expert

testimony.5 Under Delaware Rule of Evidence 702, the Court must “determine

whether the proposed evidence is both “relevant” and “reliable” when determining

the admissibility of expert testimony.6 In determining “whether an expert has a

reliable basis in the knowledge and experience of the relevant discipline,”7 this Court

applies the Daubert standard. Rule 702 permits expert testimony if the expert’s

scientific, technical, or specialized knowledge assists the trier of fact in

understanding the evidence or determining a fact in issue. The testimony must be

3
See id.
4
D.I. 85.
5
Li v. GEICO Advantage Ins. Co., 2019 WL 4928614, at *1 (Del. Super. Oct. 7, 2019) (citing
Sturgis v. Bayside Health Ass’n, 942 A.2d 579, 583 (Del. 2007)).
6
Estate of Valdez v. BNSF Railway Co., 2020 WL 7365800, at *4 (Del. Super. Dec. 15, 2020)
(citing Tumlinson v. Advanced Micro Devices, Inc., 2013 WL 7084888, at *2 (Del. Super. Oct. 15,
2013)) (citing Daubert v. Merrell Dow Pharm., Inc., 509 U.S. 579, 597 (1993)).
7
Li, 2019 WL 4928614, at *1 (citing M.G. Bancorporation, Inc. v. Le Beau, 737 A.2d 513, 521
(Del. 1999) (adopting the Daubert standard as the correct interpretation of Delaware Rule of
Evidence 702)).
based on sufficient facts or data, be the product of reliable principles and methods,

and the expert must have reliably applied these principles and methods to the case

facts.8

Our Supreme Court has adopted a five-part test for the admissibility of expert

testimony, requiring the judge to determine whether (1) the witness is qualified in

the relevant discipline, (2) the evidence is relevant and reliable, (3) the expert’s

opinion is based on information reasonably relied upon by experts in the field, (4)

the testimony will assist the trier of fact in understanding the evidence or determining

a fact in issue, and (5) the testimony will not create unfair prejudice, confuse the

issues, or mislead the jury.9 The party introducing expert testimony must

demonstrate the reliability of their opinions.10

DISCUSSION

The admissibility of expert testimony on sexsomnia is an issue of first

impression in Delaware. Dr. Angsten appears qualified because of his knowledge,

experience, and education in sleep medicine. But the State challenges the reliability

of his report, noting Dr. Angsten did not review any information “related to the

8
D.R.E. 702.
9
Nelson v. State, 628 A.2d 69, 74 (Del. 1993).
10
State v. Phillips, 2015 WL 5168253, at *3 (Del. Super. Sept. 2, 2015) (citing State v. McMullen,
900 A.2d 103, 114 (Del. Super. 2006)).
investigation of the sexual assault . . . recorded statements of the defendant, his wife,

or the complaining witness, police reports or other associated recordings.” The

Motion raises a concern, questioning the reliability of his opinion.

Under Nelson v. State, the Court must determine whether (1) the witness is

qualified in the relevant discipline, (2) the evidence is relevant and reliable, (3) the

expert’s opinion is based on information reasonably relied upon by experts in the

field, (4) the testimony will assist the trier of fact in understanding the evidence or

determining a fact in issue, and (5) the testimony will not create unfair prejudice,

confuse the issues, or mislead the jury.11 The first and fourth factors have been met.

As a Board-certified expert in sleep medicine with 23 years of experience, Dr.

Angsten is qualified.12 Sexsomnia, as an abnormal condition, falls outside the

normal experience and knowledge of laypersons. Expert testimony would assist the

fact finders in understanding the general nature of it. The Court, however, takes

issue with the remaining factors.

As to the second factor, per Dr. Angsten’s February 3, 2025 report, he

reviewed: (a) 13 office visit notes from various healthcare providers from December

2018 to March 2024, (b) a home sleep test report from January 30-31, 2022, (c) a

11
Nelson, 628 A.2d at 74.
12
See D.I. 84, Ex. A (“Angsten’s Report”) at 1, 3.
laboratory polysomnogram interpretation from June 21, 2024, a psychological

evaluation from May 30, 2023, (d) a direct examination of the defendant on May 19,

2024, (e) the defendant’s self-reported history of sleep behaviors, statements from

the defendant’s current wife about his sleep behaviors, and (f) information from the

defendant regarding his former girlfriend’s observations of past sleep behaviors.13

Notably absent from the review are any police reports from the February 5, 2023

incident or witness statements from the alleged victim.

Regarding the third factor, R. v. Luedecke, a 2008 decision from the Ontario

Court of Appeal addressing sexsomnia, provides some guidance.14 The respondent

there was charged with sexual assault and acknowledged engaging in non-

consensual sexual relations, claiming he was asleep and unaware of his actions due

to non-mental disorder automatism, specifically parasomnia. The trial judge had to

determine if the respondent’s actions were involuntary and if they were the result of

a mental disorder, which would render him not criminally responsible on account of

mental disorder.15

The expert witness there, a sleep disorder specialist, testified that the

respondent was in a parasomniac state during the incident, acting without volition or

13
Id. at 4.
14
93 O.R.3d 89 (Can. Ont. C.A. 2008).
15
Id. at 94.
control.16 The expert’s testimony was central to the respondent’s defense, as it

provided an explanation for the involuntary nature of the respondent’s actions due

to a parasomniac state. His testimony was necessary to help the court understand

the complex medical condition of parasomnia and its implications for the

respondent’s behavior.17

His expertise in sleep disorders was not questioned at trial, and the Crown did

not present any competing expert evidence. The expert saw the respondent twice in

his office and had him complete a “detailed questionnaire.”18 He interviewed the

respondent’s mother and brother.19 Notably, the respondent spent two nights in the

expert’s sleep clinic, where his brain waves and other vital signs were monitored,

and he was videotaped while asleep.20 The brain wave activity showed abrupt

transitions from deep sleep to wakefulness, which the expert identified as a hallmark

of parasomnia.21 The expert also reviewed all disclosure documentation and

transcripts of the testimony relevant to the charge, including the victim’s statement

to the police.22 He assessed the likelihood of recurrence of sexsomnia involving

16
Id. at 98.
17
Id. at 99.
18
Id. at 100.
19
Id.
20
Luedecke, 93 O.R.3d at 100.
21
Id. at 101.
22
Id. at 100.
non-consensual sexual activity as “very small,” attributing the event to unusual

circumstances and the respondent’s lack of awareness of his condition at the time.23

The trial court found the expert’s methodologies were grounded in the

scientific understanding of parasomnia, which involves sudden unexplained arousal

from sleep, and is recognized by sleep experts as a condition where individuals can

engage in complex behaviors without control.24 The brain wave patterns observed

during the sleep clinic sessions were considered conclusive evidence of parasomnia,

as these patterns cannot be manipulated by the subject.25 The expert identified

several factors that predisposed the respondent to parasomnia, including a family

history of the condition, prior incidents, and specific triggers present on the night of

the incident, such as sleep deprivation, exhaustion, and alcohol consumption.26

The appellate court did not specifically address the admissibility of the expert

testimony in terms of whether it was correctly admitted by the trial court. But the

appellate court did not find any issue with the trial court’s reliance on the expert

testimony in terms of its admissibility.27 The appellate court’s decision focused on

the characterization of the respondent’s condition as non-mental disorder

23
Id. at 102.
24
Id. at 99–100.
25
Id. at 101.
26
Luedecke, 93 O.R.3d at 101.
27
Id. at 94–95.
automatism versus mental disorder automatism, rather than on the admissibility of

the expert testimony itself.28

More locally, the Delaware Supreme Court in Rivera v. State addressed the

admissibility of expert testimony concerning parasomnia,29 or “sleep terror,” as a

defense against a murder charge.30 The expert’s evaluation included: (1) a sleep

study conducted at Christina Hospital post-incident; (2) initial statements from the

defendant’s ex-wife’s to a detective; (3) accounts from neighbors; (4) a statement

from the defendant’s cellmate; and (5) a statement prepared by the defendant for the

expert’s review.31 Our Supreme Court upheld the lower court’s decision to exclude

the expert’s opinion that the defendant experienced a sleep terror on the night in

question.32 The Court held the sleep study showed no sleep terror episodes, and the

expert had never physically examined the defendant.33 The Court found the expert’s

opinion relied solely on the defendant’s statements and those of non-expert third

28
Id. at 103.
29
“Parasomnias are disruptive behaviors or events that affect your sleep. You might walk, talk or
make physical movements to act out a dream. You might wake up in fear or be unable to move.”
Cleveland Clinic, Parasomnias, https://my.clevelandclinic.org/health/diseases/12133-
parasomnias--disruptive-sleep-disorders (last reviewed Jan. 25, 2025).
30
7 A.3d 961, 965 (Del. 2010).
31
Id. at 966.
32
Id. at 971–72.
33
Id. at 972.
parties,34 which did not provide “sufficient facts or data” for a reliable medical

diagnosis.35 The Court noted the defendant was not prejudiced by the exclusion of

the expert testimony regarding whether he experienced a sleep terror during the

murder. Although the expert could not testify to this specific point, he was able to

present the defendant’s version of events, which included his belief that he attacked

the victim during a sleep terror. The jury was not bound by the expert’s testimony

and ultimately found that Rivera had the requisite intent to commit first-degree

murder. Thus, the Court held the trial court’s exclusion of the expert’s testimony

about the defendant’s state of mind at the time of the murder was deemed not to be

an abuse of discretion, as the testimony was not considered reliable under the

standards set by DRE 702.

So too here. Dr. Angsten’s evaluation suffers from similar deficiencies. The

2022 home sleep study, conducted over a year before the incident, showed “mild

obstructive sleep apnea” on one night and normal results on the second night.36 The

June 2024 polysomnogram, while showing some abnormalities including a low

34
The expert reviewed statements from defendant’s cell mate, defendant’s ex-wife, and other
residents living near defendant’s home. Id. at 972.
35
Id.
36
Angsten’s Report at 6.
oxygen saturation nadir, although “suggestive of ongoing sleep related breathing

disorders,” revealed no parasomnia episodes.37

Defendant argues Luedecke is informative—“Dr. Angsten relied in part on

[Defendant’s] history consisting of information provided to him directly from

[Defendant] and his wife, and indirectly from a former girlfriend of [Defendant].”38

Indeed, Luedecke provides insight on how an expert in sexsomnia should reach his

conclusion, but it is not as limited as Defendant suggests. Dr. Angsten’s opinion

about the incident primarily relies on Defendant’s self-serving statements and

accounts from non-medical third parties who are affiliated with Defendant.39 Unlike

Luedecke, where “the respondent spent two nights in [the expert]’s sleep clinic” and

reviewed “all of the disclosure documentation and transcripts of the testimony

relevant to the charge,”40 and unlike Rivera, where the expert had access to police

investigation statements from the ex-wife made shortly after the incident, Dr.

Angsten did not conduct any independent sleep study nor did he review any police

reports or alleged victim statements. His assessment is based on retrospective

accounts. Defendant’s current wife, the only potential witness, had taken muscle

37
Id. at 9–10.
38
“According to the patient, his ex-girlfriend stated that the patient would walk outside of their
home in the middle of the night.” Id. at 5.
39
Third parties include Defendant’s wife and former girlfriend.
40
Luedecke, 93 O.R.3d at 101.
relaxants and has no memory of the events. It’s also unclear from the record, but it

appears that Dr. Angsten’s assessment of Defendant’s former girlfriend’s statement

was provided by Defendant himself.41

The medical records reviewed by Dr. Angsten, while noting a history of sleep

issues, provide no insight into Defendant’s condition at the time of the incident.

Office visits from 2018 to 2024 show ongoing treatment for sleeping disorders but

lack documentation of sexsomnia episodes near the incident. The May 2023

psychological evaluation, conducted months later, also fails to shed light on

Defendant’s mental state that night.

This Court recognizes parasomnia is a medical condition warranting

consideration. Defendant may present evidence of his documented sleep disorder

history. Dr. Angsten may testify about the general nature and characteristics of

sexsomnia, including how parasomnia episodes typically manifest and potential

triggers to assist the triers of fact to understand these conditions better. But Dr.

Angsten may not testify that Defendant experienced a sexsomnia episode on

February 5, 2023 as it may create unfair prejudice, confuse the issues, or mislead the

jury—failing the fifth factor. The probative value of his testimony does not

41
Angsten’s Report at 5 (“According to [Defendant], his ex-girlfriend stated that [Defendant]
would walk outside of their home in the middle of the night…”).
substantially outweigh the danger of unfair prejudice or jury confusion.42 Dr.

Angsten himself did not have a full picture of the records in reaching that conclusion.

As in Rivera, the jury will hear evidence about Defendant’s sleep disorder and can

assess whether it raises reasonable doubt about his mental state during the incident.

CONCLUSION

Accordingly, the State’s Motion is GRANTED in part to the extent it seeks

to preclude Dr. Angsten from testifying that Defendant was experiencing a

sexsomnia episode on the February 5, 2023. The Motion is DENIED in part to the

extent it seeks to exclude expert testimony regarding the general nature of

parasomnia and Defendant’s documented medical history of sleeping disorders.

IT IS SO ORDERED.

/s/ Calvin L. Scott
Judge Calvin L. Scott, Jr.

42
Sheehan v. Oblates of St. Francis de Sales, 15 A.3d 1247, 1253–54 (Del. 2011) (citing Tolson
v. State, 900 A.2d 639, 645 (Del. 2006)).