A Stupid-Simple Way To Protect Your Attorney-Client Privilege
It's simple: keep your communications between you and your attorney confidential.
Friends and family can always be counted on to ask you how you're doing, what's new in your life, etc.
They don't stop asking when you find yourself involved in a lawsuit. They still want to check in on you.
That's sweet, sure. But it can also very quickly lead to you losing your very important attorney-client privilege if the actual answer to their questions pertains to some communication between you and your attorney, and, without stopping to think first, you quickly respond to divulge some aspect of those communications to someone who is not your attorney.
Once you do that, arguably, you waive attorney-client privilege--meaning all of your previously privileged, but now leaked, communications with your attorney would now be discoverable by your litigation opponent.
That's not good, friend.
Waiver of Privilege
That may seem drastic. But maybe it would help for you to better understand that the attorney-client privilege was only ever intended to protect confidential communications between you and your lawyer. With that backdrop in mind, this loss-of-privilege effect (a.k.a. "waiver of privilege") makes more sense, because the act of you spilling the beans to your friend makes those communications between your and your attorney no longer confidential.
The reason for the emphasis on the "confidential" descriptor of communications between you and your attorney is that we want to be able to openly, and candidly, communicate with our attorneys; and the "guarantee" of privilege protecting those communications is intended to remove any reservations we might otherwise have about just being upfront and honest with the attorneys we hire to represent us in legal matters.
Scope of Waiver
Once waiver of privilege occurs, the next big issue to determine is how broad the scope of waiver is. If it is your privilege that has been waived, then you want to argue that the scope of the waiver is limited, ideally to only the specific topic you spilled the beans about. Your opponent, on the other hand, would want to argue that the scope of the waiver was broad, maybe even boundless.
When those two arguments clash, one key, deciding factor will be how broad the disclosure itself was. For example, did you spill the beans to your friend about several communications between you and your attorney, regarding multiple topics? Or did your disclosure pertain to only one communication and, ideally, also one topic?
Another key, deciding factor will be whether your disclosure was careless. For example, if you develop a reputation during your litigation for getting drunk at the bar on Friday night and talking at length about what you and your lawyer talked about that week, because you have done that repeatedly, then your disclosure might have been "careless." In that circumstance, your waive privileged could be sweeping, which, again, friend, would not be good for you.
Exceptions To Waiver of Privilege
Before you freak out, though, keep in mind that there are some limited exceptions to the waiver rule, which permit certain disclosures by you to people other than your attorney.
Typically, disclosures by you to people employed by your attorney's law firm do not waive privilege; this exception often covers you when you share information with the attorney's paralegal, for example.
Disclosures to certain other people who are assisting your attorney in his/her representation of you--an "expert," for example– may also be excepted from your privilege being waived.
Interestingly, another exception applies to disclosures by you to a third party who "shares a common legal interest" with you. This exception, though, is more dependent on the circumstances than the other two exceptions listed here. (So, you would to want to seek legal advice on this exception especially, and probably also the other two to a lesser extent, before assuming that the exception applies; because "accidentally" waiving privilege still means that your privilege is waived.)
How To Protect Your Attorney-Client Privilege
It's simple: keep your communications between you and your attorney confidential. Even if a friend asks you how things are going, and the actual answer requires dipping into that attorney-client communication, resist the impulse to spill the beans. You don't want to risk waiver of your attorney-client privilege.