Joe Arpaio announced on Sunday – the second anniversary of his pardon by Donald Trump – that he will see re-election to his old job next year.

Arpaio, 87, is a Republican who was voted out of office in 2016 after 24 years as sheriff of Maricopa county. He said he would seek his party’s nomination again in the 4 August 2020 primary, running against his former chief deputy, Gerard Sheridan.

The winner will probably face the man who beat Arpaio in 2016, Sheriff Paul Penzone, a Democrat, in the November 2020 general election.

In office, Arpaio branded himself as “America’s Toughest Sheriff”, overseeing roundups of suspected undocumented migrants, bringing back chain gangs, erecting tent cities to house prisoners and forcing inmates to wear pink.

A federal judge cited him for criminal contempt in 2017, ruling that he defied a 2011 court order barring his deputies from detaining Latinos solely on the suspicion that they were in the country illegally.

Trump, who had carried Arizona by five points in his 2016 presidential election, pardoned Arpaio on 25 August 2017, before he could be sentenced.

In 2018, Arpaio ran for the US Senate seat vacated by Jeff Flake, a frequent critic of Trump. The former sheriff ended up with less than 20% of the vote, trailing former state senator Kelli Ward and then US representative Martha McSally, who lost to Democrat Kyrsten Sinema.

McSally was appointed by the state’s Republican governor, Doug Ducey, to fill the Senate seat once held by John McCain.

Announcing his latest bid for office, Arpaio vowed to bring back his tent city and other “popular jail policies”, and to return his controversial volunteer “posse” to its former strength.

He also said he would “continue to enforce all Arizona laws that deal with drug trafficking, sex trafficking and other crimes associated with the border and illegal immigration”.