The union has threatened to strike because the contract bid specifications does not include job guarantees for the most experienced drivers of disabled/special-needs children. The city claims that a court ruling  against “employee protection provisions” in a previous case also applies to the current dispute.

Senior drivers who work for companies who submit losing bids would have to start over again at winning companies.

Last month, the DOE released the first competitive bids for drivers of special-needs children in more than 30 years. The bids cover contracts for the 22,500 students who require special transportation.

While the city says it is trying to rein in transportation costs, many parents of disabled children fear that inexperienced drivers would add even more disruption to their children’s commute. Hundreds of parents and drivers gathered at City Hall Park on Sunday to demonstrate support for the current drivers, according to DNAinfo. The supporters were chased from the park by police, according to DNAinfo.

In October, parents of special needs children expressed frustration at a City Council hearing about the many problems their children were already experiencing on school buses, including late pickups, hours-long rides, overcrowding and frequent route changes, the Village Voice reported.

Parents say rides over over two hours are common, imposing undue hardships on children in wheelchairs or who are neurologically disabled, according to the group Parents to Improve School Transportation. In one publicized case, a 3-year-old autistic boy from Brooklyn endured a five-hour-long bus ride home from school.

Parents also worry because the new contracts include such cost-cutting measures as transporting general education students on buses with special-needs kids. “The EPP [employee protection provision] is directly linked to the safety and security of New York City school children, both general education and special education, by ensuring that the City’s most qualified, professional and experienced school bus crews are the behind the wheel transporting our children safely to and from school,” according to a release from the From Day One Coalition.

Public Advocate Bill de Blasio also backed the drivers, saying in a release on Sunday, “The City needs to stop stonewalling on safety and recognize what every parent knows: experience matters.”

Chancellor Walcott, in a letter to parents, said that “the same safety provisions that are in place today” would apply to the new contracts. These provisions include completing an initial 5-hour course and a 2-hour yearly refresher course, a clean license and letters of reference.

The city said in a release that there are no legal measures it can take to prevent a strike, as the National Labor relations Board refused to take action in a similar case last year.

Check for strike updates at www.schools.nyc.gov and 311.