Barr clearly intended to give Trump the opportunity to shape the public narrative before Democrats could comment on the Mueller Report. Barr’s effort to help Trump calls into question how he might assist the President in other on-going investigations. These investigations include the Southern District of New York investigation Trump’s payments of hush money, bank fraud, money laundering, and money donated to his inaugural committee. Although these district offices have some degree of autonomy, they are subject to the authority of the Attorney General.
Currently, the Attorney General of the State of New York is also investigating possible fraud involving the Trump organization and his now-defunct foundation. That may be the best possibility to hold Trump accountable because of Barr’s cloak of protection.
https://www.nytimes.com/interactive/2019/03/31/us/politics/trump-investigations-that-grew-out-of-mueller.html