Jury deliberations at the trial of three men charged with criminal negligence causing death in the Lac-Megantic railway disaster are into their third day.

Day 2 of deliberations passed on Friday without any questions or messages from the 12 jurors.

The jury is deciding the fate of Tom Harding, Richard Labrie and Jean Demaitre, who are charged in connection with the July 2013 tragedy in which 47 people were killed when a runaway train carrying crude oil derailed and exploded.

The three men pleaded not guilty.

Harding was the train's engineer, Labrie the traffic controller and Demaitre the manager of train operations.

All three can be found guilty of criminal negligence causing the death of 47 people, while jurors have the option of convicting Harding on one of two other charges: dangerous operation of railway equipment or dangerous operation of railway equipment causing death.