The Arizona House of Representatives has hired a Phoenix law firm to investigate ethics complaints against Republican Representative David Cook.
The House says the investigation will be led by Mark Kokanovich of the firm Ballard Spahr.
Cook is accused of carrying out an extramarital affair with an agricultural lobbyist and supporting legislation that she favored. He's denied crossing ethical boundaries. He's also accused of arranging a favor for the lobbyist's family from Pinal County Sheriff Mark Lamb. The sheriff has denied the allegation.
Kokanovich and his firm also investigated ethics complaints last year against former Republican Representative David Stringer. The firm's findings led Stringer to resign.