It is first helpful to understand the stage on which the DMV APS (Administrative Per Se) hearing takes place. It is not in court, but in one of the DMV's Driver Safety Offices. When the hearing takes place, it will be in a small room where one DMV Hearing Officer will be seated on one side of a desk and you and/or your lawyer on the other side of the desk. In virtually every scenario, the Hearing Officer is not a lawyer and has no special training in the law. Despite that fact, the Hearing Officer will act as the judge, the jury, and the prosecutor all at the same time. This is why so many people think it is practically impossible to win a DMV APS hearing--the cards are stacked.
In the typical, basic DMV APS hearing for a first time DUI, the DMV must prove three things in order to suspend your license. First, the DMV must prove that you were driving while intoxicated. Second, the DMV must prove that you were lawfully arrested. Third, the DMV must prove that you were driving with a blood alcohol concentraction (BAC) of .08% or more. At the APS hearing, you will have the opportunity to present evidence and argument to poke holes in or disprove any or all of these three elements. If you can convince the Hearing Officer that the DMV does not have sufficient evidence to prove any one of the three elements, then you win the hearing. Thus, one way of beating the APS hearing is with the substantive law.
Another way of beating the APS hearing (and the license suspension) is by way of the procedural law. The APS hearing is governed by the California Vehicle Code, California Evidence Code, California Government Code, and California's Title 17. DUI defense lawyers who know these codes and laws thoroughly have the best chance at beating the APS hearing. In fact, even if the DMV could prove all three of the substantive areas of law as described above, if the DMV does not satisfy the requirements of the California codes and laws, then you can still win the hearing and save your license.
You should be aware that equitable and other non-legal issues usually have no bearing whatsoever on the outcome of the DMV APS hearing. The DMV Hearing Officer, when making the final decision, will not consider the fact that a license suspension would result in the driver losing his job. The DMV Hearing Officer will not consider whether or not the driver has to drive his kids to school. The DMV Hearing Officer will not consider whether or not the driver has had a perfect driving record for the last 50 years up to this point. None of these issues play a role. All that matters are the legal issues as outlined above. If you have the law on your side, you can beat the DMV APS hearing and save your license.