Resuming service with the Royal Navy, Brenton was appointed second lieutenant of HMS "Assurance", a troop ship destined for Halifax, Nova Scotia, which Brenton described as "a station of all others I would have chosen, having numerous friends and relations at that place". However, having been sent ashore at Rochester in search of a group of deserters, Brenton and four midshipmen were arrested, accused by the mayor of illegally "impressing within the limits of the city". Attacked by an angry mob while being transferred to prison, Brenton later recalled being "knocked down, dragged through the street and narrowly escap with life, losing nearly all my clothes." Brenton was released after the Admiralty intervened on his behalf but "Assurance" had sailed without him and he was transferred to the 14-gun brig HMS "Speedy" which was patrolling for smugglers off the English coast.