September 17, 2012
Infinity Property and Casualty Corporation
3700 Colonnade Parkway, Suite 600
Birmingham, Alabama 35243
In connection with the issuance by Infinity Property and Casualty Corporation, an Ohio corporation
(IPACC), of its 5.000% Senior Notes due 2022 (the Notes), pursuant to and as described in (a) the Registration Statement of IPACC on Form S-3 (Registration No. 333-168605) (the Registration Statement),
which was filed by IPACC with the Securities and Exchange Commission (the Commission) under the Securities Act of 1933 (the Securities Act), and (b) the related prospectus dated September 10, 2010, as supplemented by the
prospectus supplement relating to the sale of the Notes dated September 12, 2012 (as so supplemented, the Prospectus), as filed by IPACC with the Commission pursuant to Rule 424(b) promulgated under the Securities Act, certain legal
matters with respect to the Notes are being passed upon for you by us. At your request, this opinion is being furnished to you for filing as Exhibit 5.1 to the Current Report of IPACC on Form 8-K to be filed with the Commission on the date of
this letter (the Form 8-K).
The Notes are to be issued and the terms of the Notes are to be established pursuant
to Indenture dated as of August 6, 2010 (the Original Indenture) as supplemented by the and as proposed to be supplemented by the First Supplemental Indenture (the First Supplemental Indenture) to be dated as of September 17,
2012 (the Original Indenture, as supplemented by the First Supplemental Indenture, the Indenture).
In reaching the
conclusions expressed in this opinion, we have examined and relied upon the original or copies, certified to our satisfaction, of (i) the Articles of Incorporation and the Code of Regulations of IPACC; (ii) copies of resolutions of the
Board of Directors of IPACC, and committees thereof, authorizing the issuance of the Notes and related matters; (iii) the Registration Statement and all exhibits thereto, including the Form T-1, Statement of Eligibility of Trustee of U.S. Bank
National Association; (iv) the Indenture; and (iv) such other documents and instruments as we have deemed necessary for the expression of opinion contained in this letter. In making the foregoing examinations, we have assumed the
genuineness of all signatures and the authenticity of all documents submitted to us as originals, and the conformity to original documents of all documents submitted to us as certified or photostatic copies. As to various questions of fact material
to this opinion, we have relied, to the extent we deem reasonably appropriate, upon representations or certificates of officers or directors of IPACC and upon documents, records and instruments furnished to us by IPACC, without independent check or
verification of their accuracy.
Based upon and subject to the foregoing, we are of the opinion that upon the execution and
delivery of the First Supplemental Indenture, when the Notes have been duly executed and authenticated in accordance with the terms of the Indenture and paid for in accordance with the terms of the Purchase Agreement dated as of September 12, 2012
among IPACC and the underwriters named in such Purchase Agreement, the Notes will be valid and binding obligations of IPACC.
We consent to be named in the Registration Statement and the Prospectus as the attorneys who have passed upon legal matters in connection
with the issuance of the Notes and to the filing of this opinion as an exhibit to the Form 8-K. In giving such consent, we do not admit that we come within the category of persons whose consent is required under Section 7 of the Securities Act
or the rules and regulations of the Commission thereunder.
/s/ Keating Muething & Klekamp PPL
One East Fourth Street Suite 1400 Cincinnati, Ohio 45202
TEL (513) 579-6400 FAX
(513) 579-6457 ¿ www.kmklaw.com