The CJ Hawk - FBI Thriller Series

In Book One, DEPARTMENT ECHO, Hawk finds himself removed from the rolls of the Bureau after a tragic shooting left a fellow agent dead. It wasn't Hawk's fault, but somebody had to pay. As a P.I. he gets drawn into a years old murder in Old Town Alexandria where he was one of the first officers on the scene. His investigation circles right back to some of his old foes in the intelligence community. https://amzn.to/4qUwuNc 

In Book Two, ZULU CENTER, Hawk is retained to  investigate the murder of the sheriff of Alexandria's wife. The circumstances look like several other killings. What he stumbles into is an off-the-books organization spun up to hide the identities of the nation's spooks and special operators. And with rogue operations like this, what can go wrong usually does. https://amzn.to/4qY7Rzj 

In Book Three, WASHINGTON FIELD, Hawk has a most unusual client, the FBI itself.  When an IT specialist from a consultant to a big political party is murdered, the FBI wants nothing to do with it. Hawk's old supervisor in the FBI knows something is sketchy and hires him to look into it. The coverup goes all the way to the top of the Bureau. https://amzn.to/3SViJkG