The buck stops with Mayor Michelle Wu in the senseless school bus accident that killed a Hyde Park boy, as evidence mounts that the driver should not have been behind the wheel and was driving recklessly.

Wu can’t just point the finger at the bus vendor and the driver – she needs to take full accountability for the city’s needless delay in reporting details of the April 28 accident and appoint an independent investigator to oversee the deadly incident.

But so far she is not taking any of the blame, and the failure to provide timely information about the accident smacks of a cover-up. And Boston Police and the Suffolk District Attorney are complicit.

“There are protocols and this is a case where it looks like the responsibilities and obligations of the vendor were not held up,” Wu said Thursday night.

Baloney. Those comments show a lack of leadership and transparency. She is abdicating responsibility on a major public safety issue.

Where’s the outrage over the needless death of a 5-year-old? We don’t need your thoughts and prayers, we need action to make sure no other kid is in danger getting on and off a school bus.

If this happened under the watch of Mayor Tom Menino, he would have had the CEO of the bus vendor in his office the afternoon of the accident, demanding answers.

The case, coming in the middle of Wu’s reelection campaign, could explode if evidence emerges of the city trying to protect itself from litigation over public safety. Police so far refuse to release the accident report. City officials are referring all questions to the vendor, Transdev, and Transdev refuses to comment.

Are the city school buses that carry thousands of kids every day safe? Parents of all Boston school children need to know.

“You can only make an assumption, what are you trying to hide here?” City Councilor Erin Murphy said in an interview.

Wu should be calling for an investigation of all bus drivers to see if they are complying with state certification guidelines.

The driver of the bus that killed 5-year-old Lens Arthur Joseph, a student at UP Academy, had an expired certificate to drive and may have hit several parked cars before striking and killing the boy. He also may have tried to flee the scene after the crash, saying he had to complete his run.

“The facts are important for the parents to know. Are there drivers out there who would actually hit cars and keep driving?” Murphy said.

Joseph’s family has already hired an attorney and is expected to sue the city, saying the accident “could have been, and should have been, completely avoided.”

The driver, Jean Charles, resigned from his position as an employee of Transdev, right before a termination hearing was set to start. Transdev reportedly had notified him that his certification had expired but Charles did nothing about it.

Charles was reportedly a substitute driver the day of the accident and was unfamiliar with the route.

“In the case of Lens and the bus accident, we have immediately started to work with Transdev … to ensure that our bus driver group has been appropriately trained,” School Superintendent Mary Skipper said Wednesday.

The Boston Globe reported that Charles hit two parked cars in Mattapan before the fatal accident and fled the scene, but officials won’t comment on that.

And city officials have declined to release Charles’s driving history and whether or not he had been involved in other crashes. Some city councilors are demanding the city and school department release a full accounting of the accident.

“Our BPS families deserve a transportation system that is safe, reliable and accountable,” City Councilor Ed Flynn said. “I’m calling for a City Council hearing to investigate this horrific crash and how the BPS transportation system failed once again. It’s not the time for the blame game. Now is the time to investigate, answer difficult questions and make immediate changes to ensure this deadly tragedy never  happens again.”

Flynn also said in light of the fact that Charles had an expired certificate, the city should review the safety records of every bus driver.

Transdev employs some 750 drivers and has a lucrative 5-year contract with the School Department. If they’re not doing the job, Wu should find another vendor quickly.

In another embarrassment for the Wu administration this week, the chief of staff for the Office of Police Accountability was charged with assaulting a police officer after police responded to a domestic dispute between the chief of staff and another city employee.

“Public servants are held rightly held to a very high standard and I hope everyone gets the supports that they need here,” Wu said.

BPS bus driver resigns following Hyde Park accident that killed 5-year-old boy

Lens Arthur, 5, was killed by a school bus in Boston after he exited the vehicle to return home on Monday. (Photo courtesy family)