Both Thomas Bromley and his elder brother, George, were trained in law and called to the bar at the Inner Temple. By 1555, Thomas had gained some trust and prestige at his Inn of Court and was appointed as one of the auditors of the steward. In that year his namesake, the chief justice, died, bequeathing the young Thomas an allowance of 40 shillings a year for ten years, on condition he continue his legal studies. This he clearly did, as he received the degree of Bachelor of Civil Law from Oxford University in 1560 He also rose at his Inn: by February 1563 he was a member of the parliament of the Inner Temple, like his brother George. In 1565 he was appointed attendant on the Reader for the first time, accompanying Richard Onslow, a contemporary from Shropshire who often officiated with him.