Pirates are a mentioned, but hardly ever seen part of the Galactica mythos. When they are seen, it is only as prisoners on the Prison Barge, and yet their deeds are stories that re-occur every now and then.
The term pirate, as used here, not only refers to pirates who attack shipping for profit, but also slavers, smugglers and other rogues. It even includes law abiding privateers and their ilk who continue the war against the Cylons.
[Note: Pirates in Battlestar Galactica are nothing like the Orion pirates from SFB. Orion's are organised, have galaxy spanning cartels and have organised shipyards to build their cruisers and raiders. Pirates in BSG are exactly the opposite, having no organised galaxy networks, no dedicated shipyards, and tend to fly whatever they can get their hands on.]
Pirates are marauders and others who prey apon (what they consider) the weak. This means that they will attack shipping lanes (mainly freighters and liners) and occasionally the odd civilian outpost. Military targets are invariable left alone, unless there is something that the pirates want, because the military invariable have enough firepower to make the pirates work hard for their money.
While piracy has always been a problem out on the rim of known space, some pirates have a code of honour that means that they will also attack Cylon targets where possible. However to Colonial forces, a pirate is a pirate is a pirate, and therefore to be hunted down wherever possible.
Usually this job is left to light cruisers (and indeed, the CP was created to fulfil this role), but when a show of strength is needed, Destroyers or even Battlestars are sent in to fulfil sweeps of the area. However, for this to happen, a pirate group has to have committed some serious atrocities or be a major threat.
There is no 'standard' organisation for pirates. They can be as organised as a ragtag group of ex-convicts with a couple of attack shuttles who just attack the nearest civilian transport, or they can be ex-military with a sense of organisation, discipline and tactics.
About the only constant is the size of the pirate gang, and that is something that is never big. Units which get to the size of more than a couple of converted ships tend o get hunted down before they get ideas above their station.
Pirates do not generally have a steady stream of equipment. Well, they do, it is the black market and any plunder that they can find. What they do not have, is steady access to the same source of equipment, so unlike the military who will be flying the same ships and firing the same guns, pirates will tend to be armed with a mix of weapons, and flying a collection of junk heaps.
The most common source of ships is whatever a pirate can lay his hands on. Thus the most common form of ship is a souped up freighter or commercial liner, armed with a few batteries of turbo lasers, and maybe a bit of armour. This ship will usually serve as the pirates base and place to sort out their plunder, and most will be reluctant to use this in actual combat situations. So, many pirates supplement this by getting their hands on ex-service military fighters (towards the end of the 1000 yahren war, there were still a lot of ex-service Scarab fighters in pirate hands, and more than a few Vipers), or buying generally available commercial shuttles and then arming them. While no match for military fighters, against civilian freighters, these armed shuttles can be devastating.
Another source of ships is the large amount of pleasure craft that are available to civilians, travellers and tourists. These yachts have a much greater capacity for mounting weapons and with their inherent greater speed and range than normal shuttles they can be turned into formidable ships.
There are not very many noticeable pirates out there - the successful ones are the ones that are not known too well and thus can hide in a port when the heat is on. The unsuccessful ones are the ones that make a name for themselves, and then they are hunted down.
However, there are always exceptions, and these are listed here:
Running a pirate game is very easy and very similar to running a normal game, the big difference is one of scale. While a fleet game will have multiple capital ships running up against Cylon Baseships with fighter flights everywhere, a pirate game will have flights of fighters and shuttles, usually with one counter per craft.
The large scale fighter rules can be very useful for running this. About the only time when capital ships will get involved is when a pirate gets out of hand and the Colonial (or Cylon!) fleet sends a group of warships to put the situation back under control.
However, some ideas:
Pirates get captured, and sometimes the loyalty amongst thieves means that they will try and get their captured comrade back. This can involve a few attack shuttles attacking the lone prison barge (and maybe its escort of a few Vipers), and then a boarding action and retreat. Obviously the Colonial player will want to keep the prisoner, so guards are highly recommended.
The biggest way to get a profit (and reputation) is to launch a sneak attack against a civilian convoy, the object being not to destroy all the freighters, but to capture them and steal their cargo. Escorts, of course, need not be kept.
And sometimes when pirates need putting back in place, the Colonials will send in the big ships, and sometimes when they do, the pirates get too big for their boots, and (admittedly rarely) attack the hunter. This is good for swarms of fighters and shuttles, but it will be costly for the attacker. Best played (as most pirate games are) at a scale of 1 counter per fighter or shuttle.
And when the pirates do get too big, then the big guns come in and assault the pirate haven itself. This can be anything from a small ground base, to orbital station. When this happens, the pirates are usually on a holding action and will attempt to flee instead of selling their lives dearly. Usually.