The revelation that the Capitol mob - covered in emblems of extremist groups - included off-duty law enforcement officers possibly assisted by working police is escalating pressure on sheriffs and police chiefs nationwide to root out staff with ties to white supremacist and far-right armed groups. Law enforcement leaders have faced criticism in the past for failing to police their own officers’ involvement with extremist groups. However, the selfie photos that off-duty officers took inside the Capitol during the violent siege, which left one police officer dead and dozens of others injured, were a wake-up call for many who have...