In Michigan, it is illegal to chemically sterilize or trap and relocate deer. I am not sure about the legality of surgical sterilization. Sterilization has been effective at reducing closed deer populations, but has not been tried on a population as large or geographically unconstrained as Ann Arbor's. The efficacy of such a program could be worth investigating as part of a long term deer management strategy, but do to legal, financial and logistical hurdles, it would be at least a couple of years before once could be undertaken.
In our region, the most popular way of dealing with overabundant deer in parks and cities is through the use of sharpshooters. This tends to cost much less than sterilization. Sharpshooters are able to reduce deer populations and densities quickly. They do attract backlashes. Also, long term management of deer populations requires continued culling. Just something to keep in mind as we watch the city council meeting tonight.
You can read more on Ann Arbor's Deer Management Project Page Previously: