I got an email the other day, adressed to me with a mailing list of all the other Product Managers from our site in cc, that started with the words: “Actually, that’s completely wrong.” It was referring to my previous mail to a small group where I had made a comment about the readiness of a particular component to be integrated. It wasn’t just the arrogant, schadenfroh tone that irked me, but the sudden inclusion of the complete mailing list in cc. “Hey look, everyone, he was wrong!”

When you put people in cc on an email, you are making a statement. Always. The cc list can completely change the meaning and intent of an email… Who you include is often almost as important as what you say. So please be careful…

If you write to a colleague to give not-so positive or negative feedback, and you put their manager in cc, it is an escalation. If you don’t put their manager in cc, it is colleague-to-colleague feedback which has a much lower chance of provoking a defensive reaction.

If you write to a colleague to give positive feedback and you put their manager in cc, it can often increase the weight or worth of the feedback significantly.

When you answer an email with a reply all, especialy when you want to critisise or disagree with a point of view, etc, including everyone is a a statement that you want everyone to know that you disagree. This can sometimes be constructive, but if you intend to attack an idea or point out how someone was wrong, it can quickly look immature and cheap. 

Replying all to point out someone’s failure or weakness is like when you used to run to mum and dad as a child to tell on your sister whe she did something she wasn’t supposed to. It might feel satisfying for a minute, but at the end of the day you will end up looking like a child.