Well, I could be wrong, but I'm guessing they found something more recent than 3 years ago.
You don't say what type of material they found, so it's possible it was that long ago and so inappropriate that they decided it would be best, as far as their liability in some way, to terminate him.
All I know is that every job I have had has a zero tolerance policy for using company equipment for personal purposes. Period. Not even on our breaks. I have never been tempted to do anything personal at work that would jeopardize my employment. Frankly, I've been surprised at the number of moms who say they are on Mamapedia at work. No one where I've ever worked has time for that and plus, it's a terminable offense.
I don't know what your husband's position at the grocery store was, but I know people who've worked in grocery stores since they graduated high school. I know people who work in the pharmacy of grocery stores. You simply do not just surf around on the computers. You don't check your personal e-mail while placing produce orders and you don't google sales on flat screen TV's in between filling prescriptions.
This is very upsetting and you have every right to be freaked out about it. However, I think your husband should really talk to his district manager about damage control as far as giving him a decent reference that focuses on his many years of service to the company. Not knowing what he did exactly, I would hope that they would be willing to do that.
As far as unemployment, his employer can fight it. To receive unemployment, you are supposed to have lost your job "through no fault of your own".
Being in direct violation of company policy could make him ineligible if his employer states the reason for his termination. The only thing he might have in his favor is that it truly DID happen 3 years ago and they have NO proof that it's happened since.
I work in HR. We are very careful about wrongful termination, etc.
Your husband's employer was either coming up with an excuse to get rid of him, or I hate to say it, they found something more recent than you're aware of. If he's had zero policy violations in 3 years, I don't see why they would use that as an excuse out of the blue to terminate someone after that many years.
I wish you the very best and I hope I'm wrong that they found something more recent.
He lost his job. These things happen to people who have never done anything wrong so he just needs to get busy looking for another position, talking about damage control and putting a spin of some kind on it so he can get another job.
He certainly had longevity going for him so that's a plus.
No offense for anything I've said and I hope it all works out.