Your point? The Potus appoints them and is supposed to be nonpartisan.
Yes, there is an ongoing fascistic coup in the US, I know. I am pointing out that almost all criminal investigation is at the state and local level.
But the issue with the partisan Justice department is that the Potus can issue an executive order commanding the Justice department and states to prosecute and focus on specific crimes. So it’s not entirely separated from state level prosecutions.