Tammy Kingdon.

Tammy Kingdon. Photo: Courtesy Channel Ten

A jury deliberated for only three hours before convicting the partner of a notorious Perth bikie of stealing trust fund money set aside for the daughters of two dead Coffin Cheaters gang members.

Tammy Cherie Kingdon, partner of Finks member Troy Mercanti, was yesterday found guilty on four counts of stealing and one count of property laundering before District Court Judge Henry Wisbey. She was granted bail because she is the sole carer of two children and will be sentenced on December 21.

Kingdon faced Perth District Court accused of the theft of more than $53,500 from four Commonwealth Bank trust accounts set up after Marc Chabriere was gunned down in 1998 and Richard Vickers was killed in 2000.

At the time Mercanti was a member of the Coffin Cheaters and a best friend of Mr Vickers, leading to Kingdon becoming trustee of the accounts.

Mercanti was later ousted from the club after falling out with members and became a nominee of the rival Finks gang in 2008, seven years after the accounts were established.

In August 2008, Kingdon withdrew all the money, putting it into one account in her name and using it to buy a property in Balga. That property was leased to the Finks two months later, who used it for their headquarters.

Her defence barrister Stephen Shirrefs yesterday told the jury his client did not steal the money because she was the assigned trustee and used her judgement to invest the money in property during the Global Financial Crisis.

"We have no evidence at all as to the nature or terms for the money that she held in trust," Mr Shirrefs said.

He said the Trustee Act 1962 did not prevent his client from combining the trust fund money with other funds and investing it in real estate.

But state prosecutor Carmel Barbagallo said buying the property was an "investment in trouble" and that Ms Kingdon's loyalties changed after her partner defected to the Finks.