A Quebec daycare worker accused of shaking a baby boy who suffered brain damage has been acquitted of aggravated assault.

Sandra Davidson, 32, was acquitted Thursday on all charges in what was known as the shaken baby case, with Quebec Judge Jean-Pierre Bonin ruling there were sufficient reasonable doubts about the facts.

Davidson was accused of shaking the baby boy when he was 10 months old and under her watch at her daycare in Anjou, a northeast Montreal borough. She denies having shaken the child on Aug. 6, 2004.

At trial, the boy's father testified his son came home ill that day after spending time at the daycare. Davidson told the court she had noticed the child was sick, called Quebec's health information line to check on his symptoms and was told he had an upset stomach.

A nurse at the information line testified she told Davidson to call emergency services after the daycare worker described the symptoms.

Davidson never called 911, and the toddler's parents took the boy to hospital the following week. He was eventually diagnosed with shaken baby syndrome, a condition the Crown alleged was caused by Davidson's care.

The boy, now four, lost vision in one eye, suffered brain damage, still wears diapers and has the vocabulary of an 18-month-old.

Bonin ruled that reasonable doubt was raised in contradictory testimony provided by two expert physician witnesses.

A pediatrician at Ste. Justine Hospital testified that shaken baby symptoms are immediate and if the toddler was sick, he was likely shaken right before Davidson called the health line.

The defence's expert witness testified the child could have been shaken a couple weeks before the pivotal Aug. 4 date.

Davidson refused to comment on her acquittal. The Crown said it is convinced she is guilty and may appeal the acquittal.