If you don't subpoena the officer then they go ahead with out the officer and base the decision on the paperwork submitted. You shouldn't be handling this without an attorney since this is your license at stake, and you only get one chance. You may or may not want the officer there. You may or may not want the video. You may have defects in the paperwork. A trained attorney can help you with this hearing and I don't suggest you proceed without hiring an attorney.
Mr. Epifanio is absolutely correct - you should not try to do this on your own because this a very complex area of law with many technicalities. Often, even police officers do not get the law right at DMV hearings or in DUI cases.
He is also correct that there might be reasons why you don't want the officer to be subpoenaed for the hearing. But to answer your question, the DMV hearing officer is allowed to rely only on the affidavits and paperwork submitted by the officer and does not need the officer to be present to make a determination. The only thing the DMV hearing officer needs to determine in order to validate your DL suspension, is whether or not the officer had "probable cause" to effect a lawful arrest and subsequently ask you to give a breath test. They can rely solely on the paperwork and affidavits submitted to them from the officer to do this.
My answers on Avvo.com are intended to help clarify the legal process in your situation to the extent possible on this website. Criminal law can be very complicated and very serious. Every case is different and my answers are not intended to serve as legal advice unless so stated. If you have been charged with a crime you could be placed on probation or face incarceration. Please contact an attorney if you think you need legal advice in a criminal matter.
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