The Crown Office is considering a report into police handling of the Bradley Welsh case.
Police Scotland referred themselves to its own watchdog after the murder.
The trial heard police were aware of threats against Welsh a month before he was killed.
Supergrass Dean White alerted officers to the plot by Orman in two calls in March 2019.
White, who is under witness protection, told cops a man named Sean was planning to kill the former boxing champion.
Did you know you can keep up to date with the latest news by signing up to our daily newsletter?
We send a morning and lunchtime newsletter covering the latest headlines every day.
We also send coronavirus updates at 5pm on weekdays, and a round up of the week's must-read stories on Sunday afternoons.
Signing up is simple, easy and free.
You can pop your email address into the sign up box above, hit Subscribe and we'll do the rest.
Alternatively, you can sign up and check out the rest of our newsletters here.
We revealed the shooter, now identified as Orman, was paid £10,000 to carry out the killing.
During a frantic 101 call to cops weeks before the murder White told the male operator: “They are wanting to go for Brad Welsh next.”
The operator asked: “Who is Brad Welsh and where does he live?”
White replied: “He’s a guy who works in a gym.”
The operator promised to pass on the information but police did not act on the tip-off.
White told how he also revealed in a second call where the gun that would be used was being kept.
But when armed cops raided Orman’s house they came out empty-handed. Orman claimed he was hiding in the attic when police attended.
It is not known if police tipped Welsh off about the murder threat or offered security advice.
Last night the PIRC said its probe had concluded and the report is with the Crown Office.
Police chiefs last night said they would discuss their handling of the case with Welsh’s family.
Assistant Chief Constable Judi Heaton said: “Our thoughts are with Bradley’s family.
“Police Scotland carried out a thorough, robust and professional investigation into Bradley’s murder and I hope today’s conviction and sentence helps to bring his family some degree of comfort.
“While Sean Orman was the only accused in this case, we believe he was acting with others.
“I appeal for anyone who has not yet come forward, or who has information, to contact Police Scotland’s Major Investigation Team.”