The best way to lie is not presenting false facts, it's curating facts to suit your narrative. It's also often that you accidentally lie to yourself or others in this way. See a great many news stories.
There is no such thing as "objective" because it would include all things, which means it could not be perceived by anyone.
It's for indicating what's in scope for debate, and what's settled. No need to invoke "Truth". Being too stringent about objectivity means that everything is always in scope for debate, which is a terrible place to be if you want to get anything done.