A provocative African-American sheriff, David A Clarke of Milwaukee County, has announced that he will accept a position as an assistant secretary in the US Department of Homeland Security.

Although he is registered and has run campaigns as a Democrat, Clarke is a staunch supporter of Republican President Donald Trump and his views align with conservative rightists.

Clarke, who often wears a cowboy hat or elaborate military insignia, has become a regular guest at right-wing media outlets and often rails against abortion, the Black Lives Matter movement, gun control and Muslims.

Speaking to a local radio programme recently, Clarke claimed he will be working in Homeland Security's department for partnership and engagement.

But the Department of Homeland of Security said on its official Twitter account that the appointment is yet to be official.

Sr. positions are announced when made official by the Sec. No such announcement w/ regard to the Office of Public Engagement has been made. — Homeland Security (@DHSgov) May 17, 2017

If the appointment moves forward, Clarke will join the swath of Trump-appointed officials who aim to introduce increasingly hardline right-wing policies, including Attorney General Jeff Sessions, Trump's chief strategist Steve Bannon and Secretary of Education Betsy DeVos.

Asked whether his controversial opinions would inform his approach to the job, Clarke told Al Jazeera: "Assistant Secretaries do not set policy or agency direction. They carry out policy and directives handed down by the Secretary of DHS."

So what are Clarke's views on some of the most pressing issues facing the US?

Black Lives Matter

Clarke has on several occasions attacked the popular civil rights movement Black Lives Matter (BLM), which spread across the country in recent years in response to the disproportionate levels of police violence targeting African Americans.

Proclaiming that the US was in a state of civil war in a July 2016 op-ed in the political news publication The Hill, Clarke decried BLM as a "revolutionary Marxist" force that seeks "guerrilla urban warfare against police".

He condemned former president Barack Obama for not declaring BLM an "enemy" of the state and likened the group to the Islamic State of Iraq and the Levant (ISIL, also known as ISIS).

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In response to Clarke's announcement, BLM co-founder Patrisse Cullors pointed out that at least four people have died in Milwaukee jails under his watch and that he has continually worked to increase policing in communities of colour since assuming the country sheriff position in 2002.

"If true, it would represent an overt attack against Black Lives Matter and black and brown communities across the country and the globe by the Trump administration," Cullors wrote.

Civil liberties

Clarke has advocated expanding the scope of the Guantanamo Bay prison and suspending habeas corpus, effectively introducing limitless detention without charges.

"We are at war. Homegrown radicalisation has the enemy inside our borders," Clarke wrote in his new book, as reported by Milwaukee's Journal Sentinel in November.

"Islamist radicalised Americans are not criminals; they are enemy combatants."

Is the FBI afraid of charging Americans giving aid or support to ISIS with Treason? They forfeit their US citizenship and held at Gitmo. — David A. Clarke, Jr. (@SheriffClarke) December 18, 2015

He urged law enforcement "to scoop them up, charge them with treason and, under habeas corpus, detain them indefinitely at Gitmo [Guantanamo Bay]".

Gun control

Clarke, who often boasts of his membership of the National Rifle Association (NRA), a pro-gun lobby group, has lashed out at Democrats who push measures to tighten the restrictions on owning and carrying firearms.

Speaking at the NRA Leadership Conference in May 2016, Clarke argued that all civilians should carry a weapon for self defence.

"Don't ever let anyone tell you to outsource your safety to the government," he proclaimed. "Defend yourself in ways [that are] more advantageous to you, then dial 911."

Campaigns and groups that advocate gun control point out that firearms are the number one means by which most homicides are committed.

In 2016 alone, there were 477 mass shootings in the US, according to Mass Shooting Tracker, a group that monitors such incidents. At least 604 people were killed in those attacks.

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In a joint statement by Everytown for Gun Safety and Moms Demand Action for Gun Sense in America, the two pro-gun control groups decried Clarke's reported appointment.

"Sheriff David Clarke's reported appointment to the Department of Homeland Security is just the latest gift to the gun lobby - a continuing return on the NRA's more than $30m investment into the Trump campaign," said John Feinblatt, president of Everytown for Gun Safety.

In the same statement, Shannon Watts, founder of Moms Demand Action, said Clarke endorses the NRA's "extremist" agenda.

She said those policies "put communities of colour, women and children at increased risk - and policies that our army of volunteers will fight tooth and nail against in our nation's Capitol and in statehouses across the country".