A landmark trial begins Tuesday as the Department of Justice and a bipartisan group of state attorneys general sue Ticketmaster parent company Live Nation, alleging it engages in anticompetitive practices.

The lawsuit, filed nearly two years ago by the Biden administration, accuses Ticketmaster and Live Nation of using their dominance in the ticket market to block rivals. The DOJ and 30 state attorneys general say Live Nation locks up venues through exclusive long-term agreements, threatening to withhold artists and tours if venues do not sign those deals.

The suit also alleges that Live Nation pressures artists to use the company as their promoter in order to gain access to those venues.

The trial comes as Ticketmaster and Live Nation face public criticism over high ticket fees, which often push prices far above face value. Some artists have even turned to selling tickets in person to help fans avoid the costs associated with online sales.