Can you Jailbreak an iPhone 4 with a Bad ESN?

I want to jailbreak a phone other than mines, so that means I have to buy it off eBay. I was wondering if you could Jailbreak an iPhone with a bad ESN

It would serve no purpose, you still can't use the phone. But yes, you should be able to do so.

Yes, but since it is blacklisted, it's still a brick as far as phone calls are concerned.