He was born at Melrose in Roxburghshire to merchant Alexander Laidlaw and Helen Cochrane.
A banker, he migrated to New South Wales in 1839 and settled at Yass, where he became a partner in a general store.
[1] In 1859 he was elected unopposed to the New South Wales Legislative Assembly for Yass Plains, but immediately resigned as he realised his role as deputy postmaster at Yass, on a salary of £20 a year, was an office of profit under the crown which disqualified him from parliament.
[1] He remained active in local politics, supporting the re-election of Robert Isaacs in 1866.
[3] In 1866 he sold his store, which had now expanded to include brewery and post office, and became a pastoralist.