Don’t be silly. You’re only chayev misa if you knew the alarm owner was a jew. I’m assuming you knew otherwise. If, on the other hand, you knew it was a jew and you called the cops anyway, then you’re out of luck. )-:
I can’t say for certain that the car belonged to a Jew, but the odds are well in favor that it was a Jew’s car, since the majority of people on my block are Jews.
And, besides, I’d do the same thing again in a heartbeat (call the cops at 3 am, and not call a Bais Din). I understand that that not only makes me a moser, but an unrepentant one who is a menace to the community.
The Wolf