A lawsuit filed by families of the 17 people killed and other victims of the 2018 Parkland school massacre against a former sheriff's deputy who failed to intervene can go forward, a judge ruled, rejecting his motion to dismiss the case before trial.

Circuit Judge Carol-Lisa Phillips, in a ruling posted Wednesday, said a jury should decide whether fired Broward County Deputy Scot Peterson displayed a "wanton and willful disregard" for the students' and teachers' safety when he failed to confront the shooter during the six-minute attack inside a classroom building at Marjory Stoneman Douglas High School.

Peterson has insisted he didn't know where the shots were coming from and was acquitted last year of criminal charges, but the level of proof required in a lawsuit is significantly lower. The families, who have accused Peterson of cowardice, are seeking an unspecified amount from Peterson and the Broward Sheriff's Office, which did not argue for dismissal. Phillips hopes to begin the trial sometime this year, CBS reports.

"A reasonable trier of fact could find that the deputy's failure to confront the shooter, and failure to take any action to fulfill his alleged duty of protecting the students and teachers, while choosing to remain outside in a protected location to ensure his own safety constituted a conscious and indifference to consequences" to those inside, Phillips wrote in the ruling dated Tuesday.

At a hearing last month, Peterson attorney Michael Piper argued that his client had no legal duty to confront shooter Nikolas Cruz during the Feb. 14, 2018, massacre. Piper cited appellate court cases that say police officers don't have a legal obligation to protect others from third-party harm and cannot be sued for decisions they make during a crisis.

"People are outraged" that a law enforcement officer doesn't have such a duty, but "yes, that is exactly what we are saying. That is exactly what the law is,” Piper said.

But Phillips, in her ruling, said the extent of this officer's duty is also something for the jury to decide, saying there is a "genuine dispute" over whether Peterson had a "special relationship with students, teachers and administration" that went beyond what law enforcement officers typically have with the public.