It is not necessary to allege in the indictment the absence of the exceptions contained in subsection 18 U.S.C. § 511 (b). See this Manual at 226 (Negating Statutory Exceptions). The use of the term "unlawfully" excludes the coverage of the lawful removal or destruction of a number. A reason why you may wish to specifically describe the altered VIN is to establish with some specificity the actual motor vehicle which is the subject matter of the indictment. To prove a violation of Section 511, it must be established that: (1) the defendant knowingly removed, obliterated, tampered with, or altered an identification number on a road motor vehicle (or component); (2) the identification number was one required by the United States Department of Transportation (DOT); and (3) such conduct was not done lawfully (e.g., defendant knew the vehicle was stolen and was trying to conceal its identity).
The essence of the offense is to show a removal, obliteration, tampering with, or alteration by the defendant. Eyewitness testimony is the best evidence to prove that the defendant removed or falsified the number. Proof of a removal of a number should be easily accomplished by persons familiar with what numbers should be present on a motor vehicle or part.
Proof of the falsification of a VIN will require in most cases expert testimony. Law enforcement experts may be able to detect "concealed" numbers placed by the manufacturer on the motor vehicle. From such information, the original VIN can be reconstructed. If you know the make and model year of the motor vehicle in question, analysis of what the VIN characters for such a vehicle should have been will help establish a falsification.
In regard to the present 17 characters VINs, each character or group of characters has meaning. The falsification of a number can be established by experts from the law enforcement community, the National Insurance Crime Bureau (NICB), and the manufacturers. The meaning of the various characteristics of the VIN for a particular vehicle can be explained by these experts.
The manufacturer's production records will reflect whether a vehicle having a certain VIN was ever manufactured for that model year. If the criminal has duplicated an existing VIN from another vehicle, the manufacturer's records along with the VIN will reveal the particular characteristics of the vehicle having the original (i.e., authentic) VIN, thus permitting a comparison of the physical attributes of the two vehicles to determine to which vehicle the VIN was actually originally assigned by the manufacturer.
In most prosecutable cases, your expert witnesses will be able to establish the identity of the original VIN. However, if that is not possible, a successful prosecution should still be possible by showing that the vehicle was manufactured by a particular manufacturer, that such manufacturer always certified compliance with the DOT standard(s) (which compliance meant the vehicle had the required VIN (or component numbers)) and that the VIN (or component numbers) on the vehicle (or part) was not one the manufacturer assigned to any of its vehicles (or parts).
The evidence must establish an unlawful removal or falsification. The lawful removals can be found in 18 U.S.C. §§ 511(b) and 512(a)(3). Under subsection 511(b), these lawful exceptions do not apply if the person knows that the motor vehicle or part is stolen. Except for the area of "repair," these exceptions should cause no significant enforcement problem. The relevant portion of H.R.Rep. No. 1089 on H.R. 6257, 98th Cong., 2d Sess. 23-25 (1984), makes clear that the "repair" exception is intended for the protection of the honest body shop operator who while fixing a part does some injury to its identification number. The exception "is not intended to apply to the operators of "chop shops,' who remove such parts - not repairing or recycling them for lawful purposes." Most of the states that are parties to the interstate compact, which created the Vehicle Equipment Safety Commission (VESC), have established under their respective state laws, procedures for the restoration and replacement of missing identification numbers. See Regulation VESC-18, Standardized Replacement Vehicle Identification Number System.
For further discussion of 18 U.S.C. § 511, see this Manual at 1375.