effectively available to a substantial portion of the public....” 47 U.S.C. § 332(d). The district court concluded that the T-Mobile logo on the phone, as well as a text message retrieved from the phone referencing T-Mobile, sufficiently proved that the phone was “used by a user of commercial mobile service.” We agree. Although no case law provides guidance regarding the evidence required to prove this element of the crime, we find cases considering the evidence required to prove a defendant possessed a firearm under 18 U.S.C. § 922(g) instructive. In these cases, lay testimony from eye witnesses can be sufficient to support a finding that an object is a firearm and the government need not present expert testimony. See, e.g., United States v. Dobbs, 449 F.3d 904, 910-11 (8th Cir.2006) (<HOLDING>). Here, expert testimony is similarly
holding that to enhance a sentence because of the defendants use of a firearm the jury must find the defendant guilty of a crime involving a firearm or otherwise specifically find that a firearm was used holding that government could prove an object is a firearm without a physical examination of the object and a lay person may testify as to whether an object meets the statutory definition of a firearm holding that to apply the firearm enhancement the firearm need only reflect the context of the defendants possession and the defendants ability to use the firearm to promote the controlled substance offense holding that in a prosecution for possession of an unregistered firearm evidence of an armed robbery committed with the firearm was admissible holding that the government was required to prove that the defendant lacked a license to possess a firearm but not that the defendant possessed the firearm for any duration of time