The guild of butchers was one of the most important, and its members among the most respected, due to their importance in ensuring safe food but also they had to heft large animal carcasses, so they were also big strong men, not the sort you would want to mess with. But it seems the lack of preserving techniques led some to try to pass off unfresh meat. This was how they dealt with it in Newcastle. I thought all markets had inspectors, answering to the mayor and magistrates, so this article is rather surprising. From the Newcastle Chronicle of July 1766
We hear from Workington, that lately a quantity of pernicious flesh meat was seized in their market by the constables there, and burnt – This evil had long been complained of by the inhabitants of that town, which ’tis hoped for the future will be entirely removed, by the appointment of an inspector of the markets.