During his confirmation hearing in January, he assured senators of his independence and said he would not be bullied by anyone into doing something he believes is wrong if he takes the helm of the Justice Department. Barr, however, did suggest he might not release Mueller's final report to the public, saying that in the event prosecution is declined, the findings may not be made public.
Barr was willing to do whatever Trump asked of him, including not releasing Mueller's long awaited report.
It wasn't stated why Barr refused to release the report, but it was widely speculated that Barr was acting under the orders of the president. Even though Barr said he wouldn't be bullied, it was somewhat apparent he was taking orders from the White House.
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