(a) The commissioner may, in his discretion, suspend or revoke an insurer's certificate of authority if, after a hearing thereon, he finds that the insurer has willfully violated any material provision of this title other than those for which suspension or revocation is mandatory or has failed to pay applicable taxes with respect to a preceding calendar year as required by this title.

(b) The commissioner shall, after a hearing thereon, suspend or revoke an insurer's certificate of authority if he finds that the insurer:

(1) Is in unsound condition, or is in such condition or is using such methods and practices in the conduct of its business as to render its further transaction of insurance in this state hazardous to its policyholders or to the public;

(2) Has refused to be examined or to produce its accounts, records, and files for examination or if any of its officers or agents have refused to perform any legal obligation relative thereto or have refused to give information with respect to its affairs when required by the commissioner;

(3) Has failed to pay any final judgment entered against it in this state within 30 days after the judgment became final, or within 30 days after the time for taking an appeal has expired or within 30 days after dismissal of appeal before final termination, whichever date is later;

(4) With such frequency as to indicate its general business practice in this state:

a. Has, without just cause, refused to pay proper claims arising under coverages provided by its policies, whether the claim is in favor of an insured or is in favor of a third person with respect to liability of an insured to such third person; or

b. With like frequency and without just cause, compels insureds or claimants in this state to accept less than the amount due them or compels them to employ attorneys or to bring an action against the insurer or such an insured to secure full payment or settlement of such claims; provided, that as a condition precedent to a revocation or suspension of the insurer's certificate of authority under this subsection there has been a prior determination that the insured has engaged in an unfair method of competition or an unfair act or practice in the business of insurance; or

(5) Is affiliated with and under the same general management or interlocking directorate or ownership as another insurer which transacts direct insurance in this state without having a certificate of authority therefor, except as permitted as to surplus line insurers under Chapter 10 of this title.

(c) The commissioner may, in his discretion and without advance notice on a hearing thereon, immediately suspend the certificate of authority of any insurer as to which proceedings for receivership, conservatorship, rehabilitation, or other delinquency proceedings have been commenced in any state by the insurance supervisory official of such state.