A woman who pursued two teenage thieves through Perth's northern suburbs in her four wheel drive, causing them to be seriously injured in a crash, has avoided being sent to jail.

Debbie Bute and two teenagers on a motorcycle were involved in an accident in Hillarys in August last year, but the court heard there was no evidence Bute's 4WD made contact with the bike.

She pleaded guilty to aggravated dangerous driving causing bodily harm and aggravated dangerous driving causing grievous bodily harm.

The court was told 18-year-old Ronaldo Cockie (also known as Ronaldo Penny) and a 17-year-old boy were seriously injured.

They each faced a string of charges after the incident.

Teens stole motorbikes

The police prosecutor told the court the teenagers were among a group of five who had arrived at the woman's family home in a stolen car, and were involved in a burglary in the early hours of the morning.

Bute and her husband had woken after hearing a "loud bang".

They saw their garage door was wide open and two motorcycles were being pushed down the driveway.

One bike went in one direction, while the other bike went in the opposite direction with Ronaldo Cockie and the 17-year-old on it.

The police prosecutor said Bute and her husband decided to follow them to try to recover the bikes, to try to "see where they went".

Bute's husband failed to find his keys, while she went out in a four wheel drive and soon saw the pair.

Bute speeding during pursuit

The prosecutor told the court the teenagers were on the wrong side of the dual-lane Hepburn Avenue, heading towards Hillarys, and weren't wearing helmets.

The court heard Ronaldo Cockie pulled out an iPhone to record the pursuit before the bike hit a roundabout.

Bute, who had been speeding, also lost control, her vehicle mounting the kerb and ending up on the same verge as the bike.

The court heard the 4WD caught fire and Bute, who was injured, escaped before it was engulfed in flames.

Ronaldo Cockie, who was more seriously injured, suffered a fractured skull and had bleeding on the brain.

The court was told he had made a full recovery.

The 17-year-old had cuts and a broken collar bone.

No 'rational thought' to pursuit

The police prosecutor said while Bute's driving was dangerous to herself and others, there was "no evidence to suggest the vehicles came into contact".

He also said that Bute "at no time" was trying to harm anyone but he did call for a prison sentence.

Bute's lawyer Seamus Rafferty said his client had woken to a burglary in the early hours of the morning and didn't have time to "pause for rational thought".

He said there was "no conscious thought given to the consequences" of her actions.

"You just focus on the bike, you don't think about what you're doing," he said.

Magistrate Evan Shackleton responded "I accept her reaction was spontaneous".

Bute remorseful

Mr Rafferty read out an apology in which Bute said "I am deeply sorry for what I did."

"My actions were wrong."

Mr Rafferty said his client didn't seek to mitigate what she had done by saying she was herself a victim of crime.

Magistrate Shackleton referred to the 50-year-old's lack of a criminal record, and said there was no need for personal deterrence.

When he said he accepted Bute didn't want to hurt anybody, Ronaldo's mother Kathleen Penny yelled out.

"How did he sustain the injuries if she didn't touch the bike?" she said, before being removed from the court.

After the interruption, the magistrate went on to say "you have demonstrated clear and unambiguous remorse".

He said there was evidence of Bute's good character; she'd once taken in a homeless person she found and let them have a bath while she cooked for them.

While a prison sentence was appropriate, the magistrate said a suspended sentence was "right in all of the circumstances".

Bute's sentence of 15 months in prison was suspended for 12 months.

She was suspended from driving for two years on the GBH charge, and 18 months on the bodily harm charge.

Anger from teen's family

There was anger outside court, with Kathleen Penny saying "two wrongs don't make a right".

A group of women waited outside in an attempt to confront Bute, who was escorted away from them by police and court security.

They told media they wanted to hear the apology from her directly.

Ms Penny said Bute "should've got the minimum seven years".

"He's an Aboriginal boy and it's a stolen motorbike, something that's replaceable, what if my son would've died?" she said.

"Is his life replaceable over a motorbike?"