United States v. Shawn Dewitt, 943 F.3d 1092

Dewitt chatted on an anonymous app with an undercover FBI officer posing in a group named “Open Family Fun.”
Dewitt admitted sexually abusing his 4-year-old daughter, expressed a preference for "development age" (early‑pubescent) girls, and offered to exchange sexual images.
He sent one video and one still image of fully nude girls to the undercover officer; agents later seized his phone and found those images plus a photo of Dewitt engaged in a sexual act with his daughter.
A jury convicted Dewitt of production (18 U.S.C. §2251), distribution (§2252(a)(2)), and possession (§2252(a)(4)(B)) of child pornography; the district court sentenced him to 30 years.
Dewitt appealed, arguing (1) the government should have presented expert testimony to establish the subjects’ ages, (2) chain‑of‑custody gaps made phone evidence inadmissible, and (3) his 30‑year sentence was substantively unreasonable.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether expert testimony was required to prove subjects in images were minors	Dewitt: images were a close call and required expert testimony on age	Government: jurors can assess age from appearance and context; expert not necessary	Expert testimony not required here; jurors could determine age from images, demeanor, voice, and Dewitt's admissions/preferences
Whether the phone and images were admissible given chain‑of‑custody gap (phone left on agent's desk overnight)	Dewitt: gap undermines integrity; evidence should be excluded	Government: phone remained in secure FBI custody; reasonable precautions shown	Admission proper; imperfect chain of custody goes to weight, not admissibility, where evidence stayed in secured custody and no tampering shown
Whether the 30‑year below‑guidelines sentence was substantively unreasonable	Dewitt: sentence still too harsh despite variance	Government: district court considered mitigating factors and granted a substantial downward variance	Sentence upheld as substantively reasonable; below‑guidelines sentences are presumptively reasonable and court adequately considered mitigation

United States v. Katz, 178 F.3d 368 (5th Cir. 1999) (whether expert testimony on age is required must be assessed case‑by‑case).
United States v. Batchu, 724 F.3d 1 (1st Cir. 2013) (jurors may infer age from demeanor, voice, gait, and other indicia; expert unnecessary where indicators are clear).
United States v. Lacey, 569 F.3d 319 (7th Cir. 2009) (expert evidence not required to prove reality or age of children in pornographic images).
United States v. O'Malley, 854 F.2d 1085 (8th Cir. 1988) (defendant's own statements about ages can support an inference that pictured subjects are minors).
Salem v. U.S. Lines Co., 370 U.S. 31 (1962) (expert testimony unnecessary when laypersons can draw correct conclusions from primary facts).
United States v. Moore, 425 F.3d 1061 (7th Cir. 2005) (chain‑of‑custody requires exhibits be substantially the same; government must show reasonable precautions).
United States v. Tatum, 548 F.3d 584 (7th Cir. 2008) (presumption against tampering when property remains in police custody absent contrary evidence).
United States v. Jackson, 547 F.3d 786 (7th Cir. 2008) (two‑step sentencing review: procedural then substantive reasonableness).
United States v. Solomon, 892 F.3d 273 (7th Cir. 2018) (below‑guidelines sentences are presumptively reasonable on substantive challenge).
United States v. George, 403 F.3d 470 (7th Cir. 2005) (rarely will a below‑range sentence be deemed unreasonably high).