GuileyB,
If this was a group life insurance policy provided through your mother's employer Bank of America, the starting point would probably be the HR department for the bank if you can't find a copy of the policy itself.

You're referring to the fact that your mother worked (past tense) for Bank of America, though, so I'm also uncertain about the context here. Did your mother pass away while still an employee of Bank of America (and ostensibly still covered by their group life insurance policy)? If so, again the HR department would be a good place to start, particularly if you don't have a copy of the policy and/or don't know who the insurer is. If you do know who the insurer is, you can also go directly to that company, to notify them that your mother passed away.

If you're simply trying to track down information on the policy because your mother is still alive but no longer working for Bank of America, again your options are the employer or the insurance company, but they will almost certainly require your mother to be involved/on the phone/present if you contact them due to privacy law concerns. And it's worth noting that for most (although not all) types of group life insurance, the coverage expires when you stop working at the company. So if your mother retired out of the company, it's likely that the coverage isn't in place anymore unless she separately elected to continue it and received her own individual policy.

I hope that helps a little!