A judge has heard new medical evidence in the Colin Matchim shaken-baby case that’s been before the court for four years.

Now, Justice Wayne Dymond must decide whether that evidence should be admitted.

Matchim has already been found guilty of shaking his three-and-a-half-month-old daughter in March 2009, causing brain damage.

On Tuesday, Matchim's lawyer, Erin Breen said Dymond should consider the new defence evidence because it might impact the earlier finding of guilt.

The defence called expert medical witnesses who said there could have been an underlying medical condition that caused the baby's bleeding on the brain.

The Crown also called expert witnesses who said the trauma of being shaken likely caused the injuries.

Crown prosecutor Phil LeFeuvre said the new medical evidence is not strong enough to re-open the case.

Several doctors from the Janeway hospital testified in court that the child was a victim of shaken-baby syndrome.

Matchim had also confessed to shaking the infant.

But during the trial he recanted, saying he was told that if he didn't admit doing it, the finger would be pointed at his former partner - the baby's mother - and neither would get custody of the baby.

Nonetheless, Justice Dymond found Matchim guilty of aggravated assault.

If Dymond accepts the defence's new medical evidence, it could raise reasonable doubt and jeopardize the guilty verdict