 Various indictments from the period portray Eustace and his brothers as freelance mercenaries, hired 'by the ostensibly law-abiding...to commit acts of violence on their behalf'.Members of Sempringham Priory and Haverholm Abbey, both in Lincolnshire, seem to have made use of their services, and at one stage they were under the patronage of Sir Robert Tuchet, a major lord of Derbyshire and Cheshire.The justice Sir Richard Willoughby, another one of corrupt commissioners appointed in 1323 to arrest William Trussell and Roger la Zouch, was appointed to apprehend Eustace and his brothers Robert, Walter and John in January 1331 for allegedly stealing horse, oxen and sheep from Henry de Beaumont.