Challenges for cause may be taken on one or more of the following grounds:
1. A want of any of the qualifications prescribed by law to render a person competent as a juror;
2. Consanguinity or affinity within the fourth degree to either party;
3. Standing in the relation of guardian and ward, master and servant, debtor and creditor, employer and employee, attorney and client, or principal and agent to either party, or being a member of the family of either party, or being a partner in business with either party, or surety on any bond or obligation for either party;
4. Having served as a juror or been a witness on a previous trial between the same parties for the same claim for relief;
5. Interest on the part of the juror in the event of the action, or in the main question involved in the action, except the juror's interest as a member or citizen of a municipal corporation;
6. Having an unqualified opinion or belief as to the merits of the action founded upon knowledge of its material facts or some of them;
7. The existence of a state of mind in the juror evincing enmity against or bias for or against either party; or 8. That the juror does not understand the English language as used in the courts.