Rule 1220 Evidence of a statement is not made inadmissible by the hearsay rule when offered against the declarant in an action to which he is a party in either …

If you said something, your own words can be used against you in court. It does not matter when you said it or in what role you said it.

For example, if you were acting as a company representative when you made a statement, that statement can still be used against you personally in a lawsuit. The opposite is also true. Something you said in your personal life can be used against you even if you are now being sued in a business or representative role.

This rule exists because it is hard to argue that your own words are unreliable. You knew what you were saying when you said it, so the court allows those words as evidence.