Langridge hanged himself at CFB Edmonton in 2008 after several suicide attempts. Sheila and Shaun Fynes, his mother and stepfather, claim he was suffering from post-traumatic stress disorder due to his experiences on duty in Bosnia and Afghanistan.
The Fynes have complained that the military's investigation was biased and inadequate. They also say that the military erred in designating Langridge's next of kin and that it didn't disclose Langridge's suicide note for 14 months.
Shaun Fynes is on the witness stand Wednesday. Fynes, a former Toronto police officer and former Mountie, is chief of security and risk management for the B.C. government.
Fynes says he had a close bond with his stepson and encouraged him to join the military, and accused the military of killing his son in testimony that was often emotional and angry.
Read Leslie MacKinnon's live blog of Wednesday's testimony below.