In prosecution on unlawful possession of child pornography and tampering with potential witness, Dist. Ct. did not commit reversible error when admitting certain pornographic pictures and videos, even though defendant stipulated that said evidence contained child pornography. Gov’t. was not required to accept said stipulation as adequate substitute for showing content of pictures to jury where, as here, defendant took position that he did not know that he was in possession of child pornography or did not understand wrongfulness of receiving such pictures. While Dist. Ct. erred in failing to adequately explain any balancing process used to determine whether said pictures and videos were unreasonably prejudicial, any error was harmless given strength of other evidence against defendant. Record also supported defendant’s conviction on witness tampering, where defendant made eight telephone calls to his wife, urging her to lie for him by changing her prior statements that implicated him in child pornography possession charge.