Ind. Code § 5-4-3-2

Sec. 2. The sureties in any official bond, taken and acknowledged as contemplated in the foregoing section, shall, as between such sureties and the state, be deemed and taken to be principals; and it shall not be competent for any surety in such bond to set up, as a defense to an action brought for a breach of the condition thereof, any matter which would not be available as a defense to the principal in such bond.