Some of Robert S. Mueller III’s investigators have told associates that Attorney General William P. Barr failed to adequately portray the findings of their inquiry and that they were more troubling for President Trump than Mr. Barr indicated, according to government officials and others familiar with their simmering frustrations…

Mr. Barr has said he will move quickly to release the nearly 400-page report but needs time to scrub out confidential information. The special counsel’s investigators had already written multiple summaries of the report, and some team members believe that Mr. Barr should have included more of their material in the four-page letter he wrote on March 24 laying out their main conclusions, according to government officials familiar with the investigation. Mr. Barr only briefly cited the special counsel’s work in his letter…

Mr. Barr was also wary of departing from Justice Department practice not to disclose derogatory details in closing an investigation, according to two government officials familiar with Mr. Barr’s thinking. They pointed to the decision by James B. Comey, the former F.B.I. director, to harshly criticize Hillary Clinton in 2016 while announcing that he was recommending no charges in the inquiry into her email practices.