An Arizona sheriff known for a hard-line stance on illegal immigration won't face criminal charges for allegedly threatening to have his undocumented gay lover deported, the state Attorney General's Office said Friday.

Pinal County Sheriff Paul Babeu asked the state AG's office to investigate the allegations from former lover Jose Orozco, an undocumented Mexican.

Orozco said in February that Babeu had threatened to have him deported if he revealed their relationship.

The sheriff denied making any threats, but acknowledged the gay affair and resigned as Arizona co-chair of Mitt Romney's presidential campaign.

The scandal also forced Babeu to abandon his bid for a seat in Congress.

"The Attorney General's Office will not file charges against either Babeu or Orozco," Arizona Solicitor General Dave Cole said in a statement.

Babeu is seeking another term as county sheriff. EFE