Is a retired agent of the Federal Bureau of Investigations considered a public safety officer?

Please see the below information for who would be considered public safety officers and for more information: 

https://www.fbi.gov/about/faqs/what-does-an-fbi-agent-do-on-a-typical-day

Sentence 1 "Our agents enforce many different federal laws"

So yes by definition an FBI agent is a law enforcement officer.

The question relates only to Insurance Premiums you may have paid.  See more below:

If you are an eligible retired public safety officer (law enforcement officer, firefighter, chaplain, or member of a rescue squad or ambulance crew), you can elect to exclude from income distributions made from your eligible retirement plan that are used to pay the premiums for accident or health insurance or long-term care insurance. The premiums can be for coverage for you, your spouse, or dependents. The distribution must be made directly from the plan to the insurance provider. You can exclude from income the smaller of the amount of the insurance premiums or $3,000. You can only make this election for amounts that would otherwise be included in your income. The amount excluded from your income can't be used to claim a medical expense deduction.

An eligible retirement plan is a governmental plan that is: