Tasmin Glass “lured” Steven Donaldson to his death in a “frenzied” attack described by senior cops as “the worst they have seen”.
Detective Chief Inspector Andy Patrick led the probe into Steven’s death, which culminated in today’s verdicts at the High Court in Edinburgh.
Steven Dickie and Calum Davidson were found guilty of murdering Steven Donaldson by a jury.
Tasmin Glass, the mother of the late Mr Donaldson’s child, was convicted of culpable homicide.
DCI Patrick said Police Scotland’s Major Investigations Team quickly learned that Glass was at the centre of a love triangle involving her co-accused Steven Dickie and their victim, Mr Donaldson.
Their inquiry revealed Glass, Dickie, and his best friend Callum Davidson had “colluded” in carrying out “reconnaissance” of the sites where Mr Donaldson was brutally murdered and had “sourced weapons” to carry out the attack.
DCI Patrick said the vicious murder “could not have happened” without Glass setting it up.
He said: “From an early stage we identified that Tasmin Glass played a key role assisted by Steven Dickie and Callum Davidson.
“You can see the collusion of the three people that it has been a planned attack.
“They sourced a weapon beforehand. There was reconnaissance of the two key areas.
“That demonstrates there has been planning and thinking around this before it took place.
“Without Tasmin luring Steven Donaldson to Peter Pan Park this couldn’t have happened.
“Tasmin was present when the weapon was sourced. There were discussions prior to and following the crime.
“She was part of a course of conduct, working in concert. The crime couldn’t have occurred without her facilitating him coming to the park and the other two planning to have a weapon and go up and physically assault him at that point.
“We uncovered through the investigation that Steven Dickie and Callum Davidson were the best of pals, who went out drinking together and if they got involved in altercations effectively they’d back each other up.
“Tasmin was in some sort of relationship with Steven Dickie, therefore he had a motive.
“She was pregnant. She said in court that Steven Donaldson was the father.
“Steven was in a relationship with Tasmin that he wanted to continue with.
“Clearly she had a different view.”
Turning to the attack itself, DCI Patrick added: “This is one of the most brutal attacks I’ve investigated in my time in the police.
“There was a frenzied attack on Steven Donaldson, who wasn’t expecting to be attacked.
“He thought he was going there to see Tasmin Glass to sort out his relationship with her and possibly retrieve some of his belongings.
“He was met with two individuals who assaulted him right from the very start.
“A frenzied attack took place and he was then taken to Kinnordy Estate where the attack continued up to his death.
“We know there was a baseball bat involved – they sourced that from another individual.
“The two accused gave evidence that a knife was involved and possibly another weapon that caused the real serious injuries to the neck that we’ve never recovered to this time.
“When he was first assaulted it was through the window of the car, so it would have been difficult to have sustained the really serious injuries there.
“The hypothesis that plays out is that those final blows, the blows that probably killed him, took place at the Kinnordy Estate.
“I don’t know what goes through people’s minds when they carry out attacks like this.
“It’s difficult to understand what they were thinking.
“Steven Dickie and Callum Davidson have a history of low level violence, but Tasmin Glass wasn’t known to the police at all.
“It is very difficult to understand what goes through people’s minds when they devise a plan like this.
“There was clearly a plan given the sourcing of the weapon and the reconnaisance of these areas.
“The family and the community in Angus will find it very difficult to understand why did this need to happen.”
The detective also praised Mr Donaldson’s family for their “bravery and dignity” throughout the probe.
He said: “First and foremost our thoughts are with the family and friends of Steven Donaldson, who was the innocent victim of this brutal murder.
“William and Pamela are his parents, he has two sisters and was uncle to their children.
“It has been a heavy weight on them since this happened last June.
“I can only imagine what they’ve been through in the last nine months.
“I hope the community feels more secure knowing these violent individuals are off the streets.”