The rule states "2.3 Detective Warnings/KOS Reasons
As a detective you may issue a warning to players to not do/use something, but you must still use valid KOS reasons, and not make up your own false reasons. As with rule 2.2, you need to give at least two warnings in chat before you can KOS them. Some examples of valid detective KOS reasons are:"

It says as a Detective you must still give warnings which is why this punishment was valid.

EDIT: as Raeker has said it would be a valid KOS if you used it multiple times having been warned not to already.

The rule states "2.3 Detective Warnings/KOS Reasons As a detective you may issue a warning to players to not do/use something, but you must still use valid KOS reasons, and not make up your own false reasons. As with rule 2.2, you need to give at least two warnings in chat before you can KOS them. Some examples of valid detective KOS reasons are:" It says as a Detective you must still give warnings which is why this punishment was valid. EDIT: as Raeker has said it would be a valid KOS if you used it multiple times having been warned not to already.