Let's not be pedantic here. If something reliably happens, without any explicit ruleset like a law triggering it to happen that way, I feel it is fair to call it a "law of nature", as it occurs "naturally".
If you talk smack about someone, expect them to talk smack back about you.
If you talk smack about your employer, the employer will talk smack back about you (a lot of times, in the form of ending their involvement with you).