violence; R. L. Storey described Mowbray's "methods of argument" as exceptionally belligerent. According to Storey the duke "brought a force of men, with cannon and other siege engines, battered Wingfield's house at Letheringham, forced an entry, ransacked the building and removed valuables amounting to nearly £5,000." Wingfield deserted Mowbray in light of the continuing attacks over Hoo, and offered a bounty of 500 marks for the head of a Mowbray retainer. In November 1443 Mowbray was bound over for £2,000 to keep the peace with Wingfield and instructed to appear before the royal council the following April. The council ordered them to seek arbitration. This found against Mowbray, who had to pay Wingfield 3,500 marks as compensation for the damage the duke caused to Letheringham. He also had to recompense Wingfield for Hoo before he could get it back. It was presumably as part of these proceedings that Mowbray suffered his second bout of imprisonment in the Tower, which commenced on 28 August 1444; he was released six days later. In June 1446 Henry Howard, one of Mowbray's father's retainer, was murdered. He was visiting his sister-in-law (and Mowbray's aunt), Margaret Mowbray, at the time, as her house was only five miles (8.0 km) away. Howard's killers appear to have been retainers of John, Baron Scrope of Masham; who may have actively abetted the killing. On 18 June 1446 Mowbray oversaw the presentment of an Ipswich jury to examine the murder, but the case stalled. Scrope petitioned the King on the basis that Mowbray's proceedings were "inaccurate and inherently malicious," and as a result, the King ordered that proceedings against Scrope's men cease. At least five of the thirteen jurors were Mowbray retainers. This may have been the only occasion on which Mowbray personally sat on a local King's Bench commission as the hearing J.P. The arbitration did not resolve their feud, and in 1447 Wingfield returned to the attack. Along with another ex-Mowbray retainer, William Brandon, he assaulted, robbed and threatened Mowbray's staff. Mowbray—as Justice of the Peace for Suffolk—ordered him to keep the King's peace but was ignored. Wingfield was then committed to Melton gaol, but three hours later Brandon broke him out of prison. Mowbray successfully applied to Chancery for letters patent ordering Brandon and Wingfield to not come within 7 miles (11 km) of Mowbray. This order too was ignored, and they stayed at Letheringham (only