Is the Insurrection Act a Question of Intent?

Oath Keepers were stationed in hotel rooms across Potomac River from the Capitol. The group was waiting for President Trump to invoke a revolutionary era law called the Insurrection Act that would have given them legal standing as a militia, CNN's John Berman says. There is a defense called a public authority defense where someone charged with a crime says, hey, I thought I was following the law when I was breaking this crime, he adds.