Howard Graves was a high level executive at HTG Industrial Technologies that died not long before a series of strange deaths occurred around his secretary, Lauren Kyte.
Involvement in the X-Files
Lauren Kyte was protected by Howard Graves. After death, he had become a particular type of ghost known as a poltergeist. While ghosts are bound to one place, poltergeists seem bound to a person or are boundless.
As such Graves killed thugs sent to murder Lauren Kyte wherever she happened to be: the ATM, her home, or the office. He killed two men in the alley by the ATM to defend her and a man and woman in Kyte's home when a second attempt on her life was made.
He told her about his murder by waking her in the middle of night with the sounds of his murder and a blood filled bathtub.
However, in the final confrontation with Dorland himself, Lauren Kyte convinces the poltergeist to spare Dorland and help them find proof of his links to the terrorist group Isfahan.
The slight movement of the coffee mug of an irritated superior at Lauren's new job in the midwest suggest Howard Graves is still keeping an eye on her.
Graves is referred to as "Howard Thomas Graves" in his obituary, but as "Howard Patrick Graves" on his headstone. He is listed as having been born on March 4th, 1940 and having died on October 5th, 1993; however, this conflicts with the fact that he died "a couple of weeks" before Lauren Kyte was attacked on the night of September 22nd, 1993 (as shown on ATM surveillance footage).
This is likely a result of the episode airing on October 22nd, "a couple of weeks" after October 5th (which was a Tuesday, and was listed as such in Graves's obituary), implying that the timestamp on the ATM surveillance footage is inaccurate.