Rabies vaccines are undergoing challenge studies it is believed most offer immunity for 7-10 years if not lifelong immunity. This state regulates rabies vaccinations originally it was to eradicate rabies like all things once that happened the state just couldn't let go of the income and the control. Many other states have lesser requirements and many places you can still give the rabies vaccine yourself. The current 3yr vaccine took huge fights from the industry and there are published studies that show most vaccines confer 7-10 years of immunity.
Dont panic if the dogs have had at least one vaccine you are fine only worry if they havent been vaccinated. Also there are public records of outbreaks and in which species so check your area health dept stats rabies is no longer as common as it once was due to rigorous vaccination efforts. Now we have more issues with excessive vaccination in dogs and cats than we do with many of the diseases we vaccinate for...
now someone will come along and tell me how wrong I am

its all good I spent years discussing and researching vaccines with vets etc....the vaccine that is worthless and needs to be done about every 3 months is one for horses yet they say annual is ok...animal vaccines have undergone more testing and more continuous testing than human vaccines and most human vaccines are developed based on animal study and use...