Earlier this week the state of Illinois whipped out a lawsuit against the Dave Matthews Band and its tour bus driver Stefan Wohl, accusing them of violating state water pollution and public nuisance laws for allegedly dumping human waste from a bus into the Chicago River onto the upper deck of a boat filled with tourists.

Now, authorities have considered criminal charges against the band and their driver.

Chicago police said surveillance footage from security cameras on nearby buildings show a bus crossing the bridge Aug. 8 as a boat full of architecture enthusiast passed underneath. They claim it was the only bus to cross at the time of the incident.

'Certainly, this is the bus that discharged this fluid,' Cmdr. Michael Chasen told the press. He added that the band's driver told police he had crossed the bridge around the time of the incident but didn't admit dumping the waste. The driver also claimed his bus had been parked at the time of the mishap.

Though DMB was in town for a show, none of the band members were on board the bus at the time of the dumping.

Dave Matthews Band spokesman John Vlautin said Wednesday that the band, who heavily support many 'green' causes, was waiting to see the surveillance footage and other evidence before making any judgment.

More than 100 people on tour boat were splattered with the foul waste dumped from the bridge. Some of the passengers suffered nausea and vomiting, and five entered a local hospital for tests. But the attorney general's office said no one was seriously injured.

The lawsuit issued by the state is seeking $70,000 in civil penalties.

Howard Learner, the executive director of the Chicago-based Environmental Law and Policy Center, said criminal charges could include violations of public nuisance laws and ordinances to protect public and health safety.