PEORIA, Ill. (AP) — Caterpillar Inc. is hiring a former U.S. attorney general to help it sort out matters that sparked a federal raid on its headquarters in central Illinois.

William P. Barr will serve as outside counsel to the large equipment manufacturer. He’ll help Caterpillar review and address issues relating to Caterpillar SARL, a Swiss parts subsidiary, and tax-saving practices.

Issues with Caterpillar SARL have dogged the company for eight years, sparking a Senate investigation, shareholder lawsuits, and proposed taxes and penalties totaling $2 billion.

CEO Jim Umpleby said in a news release Thursday that Barr’s counsel will help the company maintain ethical standards.

Barr served as attorney general under President George H.W. Bush. He currently works at Chicago-based law firm Kirkland & Ellis.

Caterpillar is based in Peoria, Illinois.