Final answer:
An insurance Commissioner's duties include conducting investigations, issuing subpoenas, and administering oaths, but not typically setting insurer rates.
Step-by-step explanation:
The question refers to the duties of an insurance commissioner, a public official who oversees and regulates the insurance industry in a given jurisdiction. Among the listed options, the one that is NOT typically a duty of the Commissioner is 'Establish insurer rates'. Setting insurance rates is usually the responsibility of insurance companies, although the Commissioner's office may review and approve these rates to ensure they are fair and not discriminatory. The duties of an insurance Commissioner commonly include conducting investigations, issuing subpoenas, and administering oaths during proceedings or investigations.