Iowa Const. art. III, 2nd div., § 22
No person holding any lucrative office under the United States, or this state, or any other power, shall be eligible to hold a seat in the general assembly;* but offices in the militia, to which there is attached no annual salary, or the office of justice of the peace,** or postmaster whose compensation does not exceed one hundred dollars per annum, or notary public, shall not be deemed lucrative.
*In the original text, a colon was used, see original Constitution, Art. III, §22
**The office of justice of peace was abolished by 1972 Acts, ch 1124