He was loudly accused by the Catholics of collusion with the enemies of the faith.
Was there collusion among the major technology corporations to suppress wages for their workers?
He was master of the holy cities, and the official Moniteur Ottoman denounced his supposed plan of aiming at the caliphate in collusion with the sherif of Mecca.
Everyone was wondering if there was enough evidence to point to collusion.
They acted in collusion to transport the illegal goods over the border.
Collusion is an agreement, usually illegal and secretive, to limit open competition.
The current question is how many of the operatives will be charged with collusion with Russia?
The district attorney filed charges against the rogue narcotics officer for collusion with the drug traffickers.
In divorce law, the confession of a wife charged with adultery may be treated with circumspection and caution, for fear of collusion between the parties to a suit.