Gunman faces years in jail for shooting
damage to his liver. He survived his injuries.
Detective Sergeant Steven Brown, the officer in charge, said it was a “miracle” that the victim was not killed.
Dees, 33, had been due to be sentenced at Newcastle Crown Court last Friday.
But the court heard further medical evidence will be sought before the case can be concluded.
Dees, of no fixed address, pleaded guilty to attempted murder and possessing a firearm, namely a shotgun, with intent to endanger life at an earlier hearing.
He will now learn his fate next month.
He also admitted a charge of damaging property in relation to a Northumbria Police cell.
Judge Paul Sloan QC said Dees will be back in court, via video link, to be sentenced on May 15.
The judge told him: "I am going to adjourn your case until May 15 and you will be produced over the live link, as you have been today.
"You must attend the live link room.
“If you refuse to do so the sentence hearing could proceed in your absence.
"You understand you will receive a significant custodial term in any event."
The firearm believed to have been used in this attack has been recovered by police.
Chief Inspector Sam Rennison, of Northumbria Police, said shortly after the shooting: "Any incident of this type is likely to shock the local community, but I would like to thank the community of Washington for the way they have come together and supported officers at every step of this investigation.
"Firearms incidents are very rare in this area and I would like to reiterate we believe this was an isolated incident with all parties involved thought to be known to each other."