* This is a district court Judge’s ruling on a motion, which has not yet withstood appellate scrutiny. However the issue presented is important to capture emerging trends in the field.
Defendant was charged with one count of travel with intent to engage in illicit sexual conduct with a minor, one count of engaging in illicit sexual conduct with a minor in foreign places, and one count of commission of a felony offense involving a minor while required to register as a sex offender.
Defendant’s Motion to Preclude Encryption Evidence: The government wanted to introduce evidence that defendant used encryption techniques to conceal child pornography files on his laptop, as consciousness of guilt evidence. Defendant used an encryption program called TrueCrypt, which has prevented the government from opening the files to verify the contents therein. Notwithstanding, the government presented evidence to support a reasonable inference that some of the encrypted files are in fact child pornography.
The Defense posited that the encryption evidence is irrelevant in this case. While he conceded, in the abstract, that this evidence may be relevant to demonstrate consciousness of guilt like flight or concealment; it required evidence that the encryption took place when defendant knew he was suspected of the charged crimes and took place soon before or after the commission of the crimes. United States v. Harrison, 585 F.3d 382, 395 (9th Cir. 2009). The Judge agreed that without the temporal link, the encryption of the files could have occurred for reasons having nothing to do with the charged offense (e.g., attempt to hide child pornography because it is illegal to possess).
The government retorted that the evidence should be admissible because it is relevant to prove defendant’s intensity of interest in child pornography. This argument was based on the fact that defendant had to travel internationally, and his computer was subject to search whenever he crossed a border.
The Judge agreed that this evidence was relevant, but in conducting a 403 balancing test, found the probative value limited in the face of extreme prejudice that the jury may convict based on wrongful character evidence.