Crime and Punishment
The last couple of chapters of this book before the conclusion feel like they don't quite fit in the flow of the book, but Prestwich felt the subjects were important to cover. The first of these subjects is crime and punishment, and he begins by discussing how it's difficult to be sure what the crime rates actually were in the 13th & 14th Centuries. There are several factors that complicate the ability of the historian to draw out statistics from the records that survive. One major one is that the population numbers aren't known, for examples estimates of the population in "medieval London" vary from 37,500 through to 176,000 so expressing homicides as "% of population" is obviously problematic. Another issue is that we have no idea how much crime that was committed was actually reported to the authorities. And for those that are reported and go to court - do you count accusations of crime, or convictions? During this period there's an 80% acquittal rate so that makes quite a large difference.
But even if accurate numbers are difficult to come by you can look at trends over the period. Civil war led to increases in crime, in part due to people taking advantage of the partial breakdown of government. Political disagreements could turn into outright criminal behaviour - in the 1310s the Earl of Lancaster was involved in what were effectively a couple of private wars both against another Earl and due to rebellion by one of his tenants. This resulted in killings and destruction of property, and a general increase in lawlessness. War in general also increased lawlessness because the administration was focussed on running the war rather than running the country. And wars also lead to an increase in lawlessness in another fashion - the army was often bulked up by releasing men from the county gaols to serve as soldiers. If the war was a foreign one then initially they would be overseas, but on their return crime would increase. Another factor affecting crime rates was the harvest - poor harvests led to increased crime. Almost certainly this was largely due to poor people needing to steal to survive, but contemporary chroniclers also blamed it on men turned out of noble households when money was too tight to pay them who didn't know how to earn an honest living.
However, criminals during this era weren't just thugs and desperate poor men. There were several notable gangs lead by members of the gentry - although Prestwich doesn't mention it this section of the chapter brought the Robin Hood legend to mind. Members of the clergy were also involved in criminal activity. Although sometimes this isn't so much that somebody actually was a cleric, instead it's someone who has successfully claimed to be clergy so he's tried in the church courts rather than the lay ones (punishments were less severe, see below). The senior clergy were also involved in the same sorts of crimes as the nobility - both the gentry gangs and the sorts of fraud and violence indulged in by the aristocracy. Women also committed crimes, but statistically speaking they were different sorts of crime - less violence and more things like receiving stolen goods. They were less often accused of crime in the first place - only about 10% of accusations recorded were of women. Prestwich doesn't say, but I wonder if this is because women weren't (entirely?) legally separate from their husbands or fathers.
Maintenance of public order was an important function of medieval government, and there were a variety of mechanisms to achieve this. I got a bit bogged down in the details when this section of the chapter and I'm not quite sure I've got a grasp on the big picture. I think Prestwich discusses country wide courts first. At the start of the period are courts called "eyres" which aren't popular (I'm not sure why) and their use decreases over time - this was a regular visitation by royal justices to the whole country, which theoretically happened every 7 years. It appears you could pay a fine (collectively) to avoid having one sit in your town, and later kings were more interested in getting the fines than actually holding the courts. As they faded out of use other alternatives arose. One of these was that litigants could take civil cases to Westminster to the court of the Common Bench. The assizes circuits, which start from 1273, were another alternative for civil cases. Criminal case were passed to the justices of gaol delivery, or to specially commissioned oyer and terminer courts ("to hear and determine"). During this period there was also increasing use of Keepers of the Peace, a role that eventually developed into Justice of the Peace. These were local men, normally magnates or knights, who were employed to hold courts when the assizes justices weren't able to complete their circuits (during times of war for instance when money would be diverted from domestic matters).
The courts were more effective in theory than in practice. Convictions did not often happen, wrongdoers might misuse the legal system to accuse their victims (frequently successfully to at least some extent). Although there is no widespread evidence for bribing or intimidating juries they often failed to convict people even when there appears to be much evidence for their crimes. Prestwich speculates that maybe in some cases they were put off by the harsh penalties that would be applied to a convicted criminal. Men could also escape severe punishment if they successfully claimed to be clerics, sometimes they had to take a reading test but more often they just had to have the bishop's official agree with them. Which is obviously open to corruption! Clerics were tried in the episcopal courts which didn't hand out as severe penalties as the secular ones. Some of the accused never appear in court, having fled before the case was heard - there's generally a higher conviction rate in those cases.
Punishments varied. Hanging was the usual punishment for a felony. At the beginning of the period even minor thefts could end up with a hanging, but in 1279 a statute was passed setting a minimum value for imposing this felony. Pillorying was a common punishment for those sorts of minor crimes. If you refused to plead you could be punished by peine forte et dure, ie crushed by heavy rocks - which meant your family could inherit your property (unlike if you'd been convicted and hung). Imprisonment was also often used for minor crimes, or for when a fine could not be paid.
Prestwich finishes the chapter by noting that although the problem of crime & punishment during the period was great there was nonetheless no complete breakdown of law & order. He also relates an anecdote that hints at the romanticisation of crime that would lead to later legends like that of Robin Hood, or the concept of dashing highwaymen.