REVERE-Police unions have agreed to contracts authorizing random drug testing, giving the chief oversight on detail assignments and providing $295,000 in raises through 2010.Some of the money for raises has been set aside in the city budget but Superior Officers’ Association President James Guido acknowledged Mayor Thomas Ambrosino may call unions back to the bargaining table to revisit raises if “things get bad.”An Ambrosino letter to the City Council hinted that call could come sooner or later.”I expect that, in the very near future, I will be engaging each of the municipal unions in discussions involving the deferral of future benefits for the purpose of avoiding significant reductions in personnel.”Ambrosino earlier this month said he is bracing for reductions next July, possibly as early as January, in state money to the city.In his letter, Ambrosino explained random testing provisions in the Revere Police Employees’ Association and Revere Police Superior Officers’ Associations pacts are tied to contractual education benefits.Under a state law called the Quinn Bill, police are paid to advance their educations. Critics want the law scrapped to save taxpayers’ money. Ambrosino, in his council letter, said the unions agreed to random drug testing in return for Quinn Bill protections.Under both contracts the city agrees to continue paying officers the education benefit even if the law is revamped and state reimbursement payments are halted.”Everyone is grandfathered in,” said Guido.Superior Association members will be subject to random testing starting in July while testing will not begin for Police Employees’ Assocation members until, in Ambrosino’s words, “there is a need for Quinn protection.”Random testing is a controversial public safety personnel issue, especially in the wake of two Boston firefighters’ deaths that prompted questions about firefighter alcohol and drug use.”I’ve been fighting for random drug testing for 10 years,” Councilor at large Anthony Zambuto said.Police details came under fire this year when Gov. Deval Patrick proposed stripping them from state roads to save the state money. Both the superior officers’ and patrol officers’ contracts give the police chief “discretion to determine the appropriate level of police service.””It puts it in the chief’s lap to decide what is reasonable,” Guido said.