Law and order
Crime
Galle is not a dangerous place. The most likely crime you are likely to encounter is burglary. Thieves usually look for small valuables such as cash of jewellery. An unpleasant twist in Sri Lankan burglary is the risk of being held up at gun-point in your own home, but this, so far, has remained a rarity in Galle, although quite a common crime in Colombo.
Car crime is fairly rare, and is largely restricted to the theft of expensive vehicles (rather than vandalism, or theft of radios, etc.).
Alcohol
Because the majority of Sri Lankans are Buddhist there is a very strong anti-alcohol movement in the country. There is credible support for complete prohibition, backed by the government.
At the moment alcohol cannot be sold on poya (full moon) days, and at other times decreed by the government. There are also limits on how much alcohol may be transported, even for private consumption.
Criminal law
Sri Lankan criminal law should hold few surprises, but there are a few things you need to be aware of. If you are driving a car that is involved in an accident that leads to a death or injury it can be very difficult to clear yourself. You can easily end up in jail even for a death that was not really your fault.
Civil law
The major problem with civil law in Sri Lanka is that the courts have a large backlog of cases, so it can take many years for cases to be heard. There is also cheap and fast procedure for smaller cases (such as the small claims court in Britain).
The result is that it is often not worth pursuing enforcement of your legal rights, and many dishonest people benefit from this.
This is partly compensated for by the importance of reputation in Sri Lanka: people will act decently not because they are worried about being sued, but because they have a reputation to lose.