WARN only applies to notice, not to severance pay. As far as I know, even in a mass layoff situation in CA like this, they are not required to provide any compensation. You could look at it as "hey we're going to fire you in 60 days per WARN, so just stop working now and we'll pay you for that time" but it's not quite the same - they could just notify them, make them work the 8 weeks and not provide any actual severance pay.
While there have been cases of that the average person is going to fullfil their obligation and collect the check. Any manager that really is concerned about theft and sabotage in that scenario should not be a manager. Employees steal and sometimes sabotage while gainfully employed too.
My point was that risk already is there. That person that got passed over for a promotion for instance. It only takes one that is still employed at a company.
It is about a notice, but once you lay off a person it is a liability to give them access to internal systems. So majority of companies turn it around and make it look like that's also part of severance. It makes them look better and they follow the law. There is no requirement to pay severance anyway.
