Prospective clients frequently ask how their NY ticket will affect them in their home state. Since it's next door, we get this question a lot from Massachusetts drivers. One of the best places to get the answer to this question is your state's DMV. In Massachusetts it is known as the RMV - Registry of Motor Vehicles.
This post is about Massachusetts, but for a more general discussion, see my Do Points Transfer post.
The RMV says that out-of-state tickets will count against you. It's in Chapter 2 of the RMV Drivers Manual (a pdf file). Here are some quotes from that:
Certain traffic offenses you have committed in other states will be placed on your driving record and treated by the RMV as if they had occurred in Massachusetts.
... [O]ut-of-state violations count toward possible license suspension and automobile insurance surcharges. ...
[T]hese offenses will be treated as if they occurred in [MA] if they are a “like” offense. ... RMV will look at what conduct the other state's law prohibits ....
RMV [will] apply Massachusetts license suspension rules to any [such] out-of-state violations ....
A lot of states follow this approach. One reason to hire our firm is that we look at your state's rules to see what reductions would have the lowest impact in your home state. Then we use that information in negotiating a deal for you. This is important. One of the most common reductions for simple tickets in NY is actually worse than a low speed for drivers in some states, such as NJ and FL.
For those interested in MA, see my post about Massachusetts Traffic Court.