The driver of the speeding Green Line trolley that rear-ended another train in July had been suspended at least six times in his seven years on the job, including at least four prior violations for speeding, according to a police report filed in court.The driving record of T driver Owen Turner was referenced in the MBTA Transit Police report filed in Brighton District Court, where police sought charges against Turner for the crash that injured 27 people. Brian Kane, executive director of the MBTA Advisory Board, questioned by Turner was still working."He's been caught multiple times before. And I really wonder why he was behind the controls of any MBTA vehicle," he said in an interview with 5 Investigates.Turner's disciplinary record, laid out in the police report, shows he was given a "final warning" after speeding in 2016. In 2017 he was "terminated with pay," and then back on the job months later. In 2020 he had three more speeding violations. "I blame the MBTA. I blame the Carmen's Union and I blame Mr. Turner. Mr. Turner had a duty to operate that vehicle in a safe and non-negligent way. He clearly did not do that. And that's why he's going to be on trial," Kane said.Federal investigators say Turner's train was speeding — traveling 30 miles an hour at the time of the crash, which is three times the speed limit on that stretch of track. According to court records, Turner told police when he woke up after the crash his left hand was on the accelerator — all the way forward. He also said he's considered to be a "fast operator."The team at 5 Investigates has learned that since 2019, 134 Trolley, train and bus drivers have been discharged by the T-only for six safety violations including speeding."I want the MBTA to explain very clearly what its actual disciplinary processes and procedures are. How is it that a person can come back to work after this many disciplinary actions? And how is it that this individual has not had to go through retraining multiple times, given his record of speeding? I want to see change at the MBTA," Kane said.Sources tell 5 Investigates that, typically, after someone is given a final warning, the T can move to discharge the operator, the union can step in and fight that. T officials won't tell us if that happened in Turner's case, and the Carmen's union did not respond to requests to comment.Turner faces two criminal charges in the case: gross negligence in managing a railroad and common carrier's gross negligence. He has an arraignment scheduled for Oct. 6.The MBTA said it is moving to end Turner's employment.