If you requested the presence of the officer at your DMV hearing, the only officer that will show up is the officer that signed the Affidavit and Notice of Revocation. However, in many DUI cases the most important testimony will come from a different officer. For example, in some cases, the officer that initially contacted the defendant will be different than the officer that is summoned to appear at the hearing. In many DUI's the basis for the initial traffic stop is the most important issue. Thus, without subpoenaing this other officer, a defendant may miss a chance to establish a defense.
In order to determine what officers were involved, you need to request discovery from the DA or the DMV. Either of these will provide you with the reports written by the officers involved in your arrest. From these documents you will be able to determine if additional officers were involved in your arrest. However, deciding whether these officers will provide useful varies from case to case.
There are two forms that you will need to fill out. The first is a "subpoena to testify." The second document is the "required statement attachment for subpoena." In the second document you must explain why the testimony you are seeking is relevant and necessary, that the subpoena will not be unduly burdensome, that the request will not delay the proceedings, and that the information or testimony subpoenaed is not otherwise obtainable before the hearing.
Once these documents are completed, submit them to the DMV for approval.
Complete Service of the Subpoena
Once your subpoena is approved, you must serve the subpoena on the individual. This can be accomplished by contacting a service processor. However, if the subpoena is for a police officer, it must be served at least 5 days before the hearing date. Otherwise, the subpoena must be issued at least 2 days before the hearing.
Once the subpoena is properly served then the subpoenaed party must arrive at the hearing to testify. If a subpoenaed party does not arrive to testify, the result may be dismissal of your case and reinstatement of your driving privileges.
Additional resources provided by the author
Colorado Department of Revenue, Hearings Division: (303) 205-5606