By Patricia Zengerle and Michael Martina

WASHINGTON (Reuters) – Questions about the murder of a Black teenager by a white police officer loomed over the confirmation hearing on Wednesday for former Chicago Mayor Rahm Emanuel, President Joe Biden’s nominee to be the U.S. ambassador to Japan.

The hearing took place exactly seven years after police officer Jason Van Dyke fired his weapon multiple times at 17-year-old Laquan McDonald.

Then-Mayor Emanuel was questioned about his handling of the case, especially the fact that a video showing the shooting was not released for more than a year.

Emanuel made a statement about the killing at his hearing. “I said then, ‘I’m the mayor and I’m responsible and accountable for fixing this, so this never happens again.’ To be honest, there’s not a day or a week that has gone by in the last seven years I haven’t thought about this,” he told the Senate Foreign Relations Committee.

Democratic Senator Jeff Merkley praised the “depth and breadth” of Emanuel’s experience, but questioned him about what he knew about McDonald’s (NYSE:) death and when.

“It seems hard to believe all those things happened and yet you were never briefed on the details of the situation when you were leading the city,” Merkley said.

Emanuel is a former member of the House of Representatives and was the first White House chief of staff when President Barack Obama was president and Biden was vice president.

Emanuel is expected to be confirmed. He is backed by most of Biden’s fellow Democrats and some Republicans. Republican Senator Bill Hagerty, who was ambassador to Japan under ex-President Donald Trump, introduced Emanuel at his hearing and urged his confirmation.

Van Dyke was convicted of second-degree murder and jailed for nearly seven years and four Chicago police officers were fired over McDonald’s death, which highlighted racial tensions in the United States’ third-largest city.