My question involves insurance law for the state of: NY

Don't have much knowledge regarding insurance situations and such, thus my question.

Driving along I stopped short due to someone ahead of me stopping short.

- I stopped way ahead of time as did the driver behind me
- Driver behind me was rear ended by the driver behind him so forcefully that it sent him 20-30 feet into my rear end.

Yet what's the best thing in my interest to do next?
'and can someone explain the true meaning of 'No Fault' in NY State?

The police who showed up stated that it didn't matter whose fault it was because of the 'No Fault' rule in NY.

I haven't reported anything to the insurance company as of yet. 'and this all transpired today.