Mark Lamb

Mark Lamb is the Republican nominee for Arizona's 5th Congressional District, an open seat. A former law enforcement officer, he was Pinal County sheriff for eight years and ran unsuccessfully in the 2024 Republican U.S. Senate primary. He won the July 21, 2026 primary with the endorsement of President Donald Trump, amid public allegations from multiple women that he sent them sexually charged messages; a Pinal County Attorney's Office review found no evidence of criminal conduct, and his campaign has denied the allegations.[2][3][4][5]

Lamb was born in Hawaii in 1972 and spent much of his childhood there, with periods in Arizona, the Philippines, Panama and Argentina; he graduated from Chandler High School in Arizona.[1] Before law enforcement, he started a paintball business in Utah and later worked in pest control, and he moved back to Arizona in 2003.[1]

Lamb's campaign website says that before becoming sheriff he served as a police officer and detective, earning recognition for gang enforcement, criminal investigations and multi-agency operations. It says his law enforcement career included local, state, tribal and federal investigations.[5] Wikipedia says he worked for the police department of the Salt River Pima-Maricopa Indian Community for six years before joining the Pinal County Sheriff's Office in 2012.[1] He was elected Sheriff of Pinal County in 2016 to succeed Paul Babeu, was re-elected unopposed in 2020, and served from January 2017 to December 2024; his campaign website describes eight years as sheriff.[1][5] He appeared on the television series Live PD and hosted its spinoff Live PD: Wanted, and was featured in Season 5 of 60 Days In. He is the author of the self-published book American Sheriff: Traditional Values in a Modern World, and in February 2021 he co-founded Protect America Now, a coalition of sheriffs.[1][6]

Lamb ran for U.S. Senate in 2024 to succeed Kyrsten Sinema and was defeated in the Republican primary by Kari Lake.[1][2][6] He entered the Republican primary for Arizona's 5th District in October 2025, after Rep. Andy Biggs chose not to seek re-election, and won the July 21 primary over Daniel Keenan, 58.7 percent to 41.3 percent. Ballotpedia lists endorsements from Trump and Turning Point Action.[1][2][3]

In May and June 2026, news reports said multiple women alleged that Lamb sent them sexually charged messages. On June 22, 2026, Pinal County Attorney Brad Miller's preliminary review found no evidence that Lamb acted in a criminal manner, and the matter was closed; Lamb's campaign has denied the allegations.[3][4]

Researched from the cited sources on 2026-10-21.