https://slate.com/news-and-politics/2019/05/barr-mueller-report-hearing-rigged-trump-prosecution.html?fbclid=IwAR2Wx7W03m7jrSRjC30cT9YkzD655a5-yEeIrl-roKjoKRe8a3ktMqiRSz0
"Together, Barr’s four rules make an obstruction of justice case impossible. The president could stand in the middle of Fifth Avenue, fire the FBI director, fire a special counsel, threaten witnesses, and instruct subordinates to lie, and he wouldn’t lose the support of his attorney general. That’s why Trump hired Barr in the first place. And that’s why Mueller’s investigation shouldn’t end with Barr’s refusal to prosecute the president. We can’t let a lawyer acquit his own client."