Disable dictation from command line

Is it possible to disable dictation from the command line, so that macOS never asks again if I want to enable it?

I know that many such things can be done using defaults write but couldn't find the right key for dictation. I'm using macOS Mojave 10.14.5.

If you are talking about not having the message box, shown below, popping up again when pressing the e.g., Fn key twice, then use the following defaults command in Terminal:

defaults write com.apple.HIToolbox AppleDictationAutoEnable -int 1

This changes the Shortcut: setting from e.g. Press Fn (Function) Key Twice to Off in System Preferences > Keyboard > Dictation, and would be the same setting that gets set if clicking the Don't Ask Again button.