According to what source? So far in my own digging, the only ones IMPLYING criminal activity/intent on the part of the Cossacks is vaguely-referenced "police intelligence," while the only real criminal "activity" I can find on the part of the Cossacks in Texas, at least, is their resisting when they are harassed and attacked by Bandidos for wearing the Texas patch on the open road, and their actions to retaliate by harassing and attacking Bandidos in return.
One of the Cossacks arrested at Waco, K.C. Massey, had already crossed the Feds and is slated to stand trial with jury selection starting July 28, because he and some others apparently had the audacity to do what Border Patrol agents refused to do, and do an armed patrol on private property in Texas to stop illegal and drug smuggling from crossing at that part of the border, where a border patrol agent fired five rounds at one of Massey's men, missing him. Even though The Cameron County Sheriff could find no violation of the law, they confiscated the weapons of Massey and his guys, who had apparently been guilty only of doing what the Border Patrol was failing to do.
Unless of course Massey and his guys were actually engaging in drug/human trafficking themselves while patrolling that bit of private property, but if so, apparently law enforcement has ZERO evidence to even accuse them of it.
Maybe the Cossacks are a gang on a par with Bandidos/Hells Angels, maybe some individuals in the club aspire to be, I don't know. I find ZERO record or even direct accusation of Cossacks engaging in human and drug trafficking, murder, and robbery.
In fact, as far as I have seen, the only things the Cossacks have actually done according to police, is to respond to Bandido harassment. It takes a few times of reading these various articles to notice it, but indeed, Cossacks' criminality is only ever implied, whereas Bandidos have a long established reputation as really bad dudes and have convictions and criminal charges to prove it.
Regardless, the whole set-up at Waco looks like ... a setup for a massacre against Cossacks on the pretense that they weren't playing nice with the Bandidos.
Correction: Massey was NOT arrested at Waco.