Civil rights advocates and scholars say the US government’s claims are troubling indicators of rising authoritarianism

After New York City comptroller Brad Lander this week became the latest prominent Democrat to be arrested while monitoring and protesting US immigration authorities, the Trump administration trotted out a familiar refrain to justify his detention.

The mayoral candidate had “assaulted” law enforcement, the Department of Homeland Security (DHS) asserted, warning “if you lay a hand on a law enforcement officer, you will face consequences”.

The accusation, which DHS has also recently leveled against a member of Congress and a high-profile union leader, have sparked consternation, particularly as videos of the incidents did not show the officials attacking officers and instead captured officers’ aggressive behavior and manhandling of the officials.