| Place of birth | Harrow, Victoria |
| School | Eden Hope State School, Victoria |
| Religion | Presbyterian |
| Occupation | Station overseer |
| Address | Winton, Queensland |
| Marital status | Single |
| Age at embarkation | 30 |
| Next of kin | Mother, Mrs Mary Sinclair, 8A Mary Street, St Kilda, Victoria |
| Enlistment date | |
| Rank on enlistment | 2nd Lieutenant |
| Unit name | 2nd Light Horse Regiment, 12th Reinforcement |
| AWM Embarkation Roll number | 10/7/3 |
| Embarkation details | Unit embarked from Sydney, New South Wales, on board HMAT A23 Suffolk on |
| Rank from Nominal Roll | Lieutenant |
| Unit from Nominal Roll | 2nd Light Horse Regiment |
| Other details from Roll of Honour Circular | "The first brigade was drawn up in close formation at the [Weli Sheik Muan] on the morning of 20 April 1917 when enemy planes bombed the troops. With no thought of his own danger he stood exhorting his men to lay down in safety. The last man lay down - a bomb fell nearby and their leader paid The Great Sacrifice." [Mother: Mary Sinclair of St Kilda, Victoria.] |
| Fate | Killed in Action |
| Miscellaneous details (Nominal Roll) | *Given name David Harold |
| Place of death or wounding | Gaza, Palestine |
| Age at death | 33 |
| Age at death from cemetery records | 33 |
| Place of burial | Beersheba War Cemetery (Row Q, Grave No. 83), Palestine |
| Panel number, Roll of Honour, Australian War Memorial | 3 |
| Miscellaneous information from cemetery records | Parents: James and Mary SINCLAIR, 8 Mary Street, St. Kilda, Victoria |