Civvies with starship guns?

[jatay3]

But holly canon says there can't be piracy due to the HUGE and EFFECTIVE imperial navy. So holly canon makes cannons moot.

Holy Canon says the Imperial Navy is huge and effective. It makes it pretty clear that it is not omnipresent.

The Third Imperium does not depend on a brittle "do what we say, everywhere all the time" ethic like the Ziru Sirka. It often overlooks local disorder to maintain political balance. Furthermore, if the huge and effective Imperial Navy did to many things outside the borders of the Imperium sooner or later it would commit an act of war against another power with a huge and effective navy. And there are still large chunks of space, in any case, where nobody's huge and effective navy has yet entered.

The Imperial navy is a huge and effective navy. It is not Grandfather.

 

[rancke]

But holly canon says there can't be piracy due to the HUGE and EFFECTIVE imperial navy. So holly canon makes cannons moot.

Actually, canon says that piracy exists. It's numbers and calculus that says that the authorities have a big advantage over pirates because the slice of the universe that has to be patrolled is so comparatively small. But since pirates are FUN, it's best not to take much account of what the numbers imply.


Hans

 

[Seriayne]

IMTU, off the cuff -

Imperium
"Defensive" weaponry is allowed on commercial ships - but since every megacredit counts, and even the turrets need maintenance, anything operating more than 10 parsecs from the border is generally unarmed. Spinal weapons and nuclear payloads are banned outright for commercial ship designs.

Extra-Imperial traders must have their ships modified to comply with these regulations, and registered -before- entry into the Imperium. Failure to do so will be seen as an attempt to 'smuggle' said weapons into Imperial space at best, and as an act of piracy or even war at worst. Cooperation in these cases will result in impounding of the vessel until such a time as the MoJ is satisfied with ship refitting, licensing, and fines and/or prison sentences of the guilty party having been resolved.

Solomani
Depending on the internal substate of the Confederation, any number of rules may be locally in place, but for the most part the 'cold war' nature of its relations with just about every major interstellar power, especially the Imperium, means that most merchanters go fully armed pretty much anywhere within 30 parsecs of a Confederation border.

Any ship owned/operated by a member of the Home Guard is pretty much expected to have their ship armed and available for auxiliary service 'just in case'. The heads of SolSec aren't too happy about this, but have accepted it as the status quo.

For the most part, the same bans against nuclear weapons and spinal mounts are pretty much the same as in the Imperium, with the exception of The New Slavic Solidarity state in Magyar sector, who's internal laws require merchants to be allowed nuclear payloads for defensive purposes. These laws date back to the Long Night and the continuation of which were part of the conditions of joining with the rest of the Confederation at its inception. SolSec is extremely unhappy about this, but a subclause to their joining precludes Confederation interference on this issue and makes secession a legal option if future regulations don't include this exception.

Vargr
YMMV as usual. Some states are just large enough to control some of what goes in and out of their core systems, and their border system defenses will react according to their internal laws and relative stability of whatever central government is in control at the time.

Society of Equals for example, has much the same restrictions as the Imperium. The Anti-Rukh Coalition oddly has a rule restricting defensive weaponry to offensive weapons only - ie. sandcasters aren't allowed. If you fill a turret, it must be with something offensive.

Hiver
"There are no restictions as such, but why would a peaceful ship want to arm itself anyway? All right, very well, if you insist. Oh, but I'm sorry, it appears the closest manufacturer of nuclear warheads compatible with your ship is backlogged supplying the Federation Navy for the next seven months I'm afraid. The next closest is *checks readouts* Dwelve, twenty-five parsecs away and requires refitting at site. That particular nest also requires you fill out their extensive customer satisfaction surveys, future reload exclusivity contract (their refitting of your weapon systems will require this anyways), and come in once every year for an ordinance check - they'll replace any warheads still under their rather generous warranty for free.

"Oh, and don't worry, the situational lockouts are quite generous in permitting your ship to defend itself with the ordinance in case of a pirate attack - the system is really quite smart and exceedingly hard to feed false data to, and any tampering will disable the system until a full investigation at Dwelve can clear the customer of any misuse of the system and reactivate it."

"Oh, you'll just take standard High Explosive ordinance? Very good, sign here and here, and our technicians will meet you at your airlock within the hour. I promise, you won't be disappointed!"

Foreven, The Beyond, Far Frontiers, Vanguard Reaches
Anything outside the Imperial client states and the Consulate(s) and other established interstellar states is pretty much wild wild west, but few besides pirates actually arm with nuclear ordinance simply for the fact that its expensive, and eventually they'll have to cross back into these larger states to do business. A few free traders and even multi-ship companies will have wilderness hideyholes one jump outside the major powers' space where they can re-arm with nuclear warheads for long traderuns into the wild.

Some independent systems look the other way simply because without these heavily armed merchants, they might not see traffic come through for weeks, months, or even years at a time. Other systems can't even enforce their will against ships with standard ship lasers and HE missiles due to lack of technology, population, wealth or sometimes all three.

 

[Patron Zero]

Smaller Spinal Mounts

Nukes and spinals are military-only. Smaller stuff is fine.

My house rules allowed for what could be viewed as 'mini-spinal mounts', essentially 'torpedo' tubes that could launch various payload carrying projectiles, restricted to vessels of 100 tons or larger.

Best to think of a fixed mount, dedicated magnetic driven rail gun-coil gun system that had offensive-defensive capacities as well as launching rescue beacons, 'message' torpedoes and scientific-exploration probes.

Said 'torpedo' tubes were capable of firing solid 'shot' ordnance directly at a target or deploying localized mine fields in the vessel's wake to discourage pursuers. Less dramatic are the use of the system to launch ECM and other passive defensive measures, 'flares', 'chaff' and 'smoke'.

Prospectors-miners found the 'torpedo' tubes an excellent means of firing core sampling 'probes' into asteroids and invaluable as form of high velocity-deep penetration tool for 'splitting' rock and ice, often referring to such as a Miner's Hammer.

 

[Starviking]

Only if X-boats go to every world at the same time all across the subsector. Which they don't...

Sure, you could set up your TU like that if you wanted and ignore the financial MegaCorps. You're the GM.

X-Boats don't normally travel off the X-Boat routes - IIRC that task is undertaken by the Scout/Courier and Merchants with mail contracts.

 

[Gojifam58]

Some have mentions that the "locals" might take offense of an armed mechantman. Personally I really doubt it since Imperial policy has always been that while they usually leave a planet's affairs to themselves, space is the Imperium's. That goes double for the prime starport as it is considered Imperial territory, thus immune to local laws.

While I'll agree that trade may be able to go unarmed in deep parts a of the Third Imperium, anyone operating anywhere within 12 parsecs of Vargr, or Solimani in my opinion, frontiers would be a fool not to arm their ship, and missles make more sence since they require les power for the damage delivered. ...about the only thing I can remember about weapon restrictions for commercial vessels is definitely no spinal mounts and don't even think about tossing a nuke. The only way Oberlindes got around that was to take their AHL it the Vargr extent, never intending to operate her in Imperial space, Im pretty sure that the other conversion kept most if not all her bay weapons but the spinal mount was pulled and the space converted to other uses.

 

[aramis]

Worlds that don't like armed merchantmen are, per imperial law, only allowed to enforce that to 100 diameters. (COACC)

They can, and some undoubtedly do, make it a local crime for a local resident to arm a merchant ship registered to that world... so locals from there would likely resort to changing their registration and citizenships to other worlds.

On the other hand, the ship itself is as potentially damaging as any major thermonuclear device, even unarmed.

 

[madmike]

British East Indiaman were almost as heavily armed as 64 gun 3rd rate ships of the line during the 18th and early 19th centuries.

As such, due to the "19th century style" of Traveller in regards to frontier worlds and light speed communications, I would certainly expect to see Civilian merchanters to be armed. Within the core sectors armed merchanters would be far less common.

In a house rule mod, the Imperial government does not allow any civilian ships to be constructed with bay or spinal mounts as these are considered to be military armament. Nuclear warheads (xray etc), Meson and PA weapons are also on the prohibited list.

The series "Vatta's War" by Elizabeth Moon is worth reading for the way she handles armed Merchant ships.

 

[Carlobrand]

Well, let's see now. Canon gives us:

a random chance of encountering pirates in space - Book 2, p35, exclusively around type C and lower starports, very roughly a 1 in 6 chance;

an assortment of pirate NPCs to draw on in Citizen's of the Imperium;

and about a 1 in 36 chance of encountering pirates under the Megatrav encounter tables found in the Imperial Encyclopedia.

So, it's clearly a part of the game.

On a more pragmatic note: the Spinward Marches at least is a pretty thinly populated frontier. Of the 439 worlds, more than half are population rating 5 or lower, and less than a third of the worlds can boast a Class A or B starport - there are 114 C's and 130 D's and E's. This is the kind of place where people are likely to play Somali Pirates, or Malacca Pirates, or what have you. A subsidized liner plying a route between two class-B ports is not going to need weaponry, but the same can not be said of a free trader delivering a special cargo to that pop-4 world with the class-D port; HE needs at least enough firepower to persuade that down-on-his-luck ex-scout to find easier meat.

If the free trader goes back and reports the encounter, the most likely response is going to be, "Did he have any distinctive markings? Weapons damage, anything like that? Anything that might differentiate him from any of the thousand other scout/couriers roaming about the Marches?" Because, as we all know, no self-respecting pirate charges into battle with his transponder codes blaring and his registry numbers visible on his hull. On the positive side, your report would likely be followed by dispatching a Gazelle to the planet for a few weeks until they're satisfied the threat's moved on.

That being said, he likely doesn't need more than the basic civilian-access firepower - lasers, conventional missiles and such. Aside from the Vargr up close to the coreward border, most pirates aren't going to have access to anything bigger than a Broadsword - a Navy captain making off with a 2000-ton 700 million credit Destroyer Escort's the kind of thing that tends to have the Navy out hunting in force until captain and ship are either recovered or very dead. So, heavy weapons is a lot of money and ship volume that could go to much more productive use doing something else.

As to whether the locals appreciate his armed ship - well, that depends. Those who have a say are also those best positioned to smack him should he misuse those weapons - that would be the class A/B starports with their anti-piracy patrol craft. Knowing that there are high risk planets nearby, and not wanting to disrupt trade to those planets, they may be willing to tolerate armed ships since they themselves are not at risk.

As for others, the typical world with a population smaller than Mayberry doesn't have much money for multi-million credit orbital defenses, or even million-credit ground-to-orbit missile systems. A whole lot of those who might object aren't going to have the ability to do much about it - if you don't have patrol ships of your own up there to set eyes on what he has mounted and to enforce your will, you don't have much say about what happens in orbit. And, once he's landed at the Starport, he's under Imperial jurisdiction.

Note that if the world can object, and does, then one hopes sincerely that most of their interstellar trade comes from other class-A and B starports, 'cause the point at which you make a merchant's life more dangerous is the point at which he decides to take his business elsewhere.

As for the Vargr - think of it as counting coup. They want your wealth. They don't have any interest in killing you unless you make trouble, 'cause they're going to go home when their little romp is done - home where the Imperials can't go without offending some local Vargr power. So, if a 2000 ton Vargr ship comes into sensor range, just give him your cargo and claim it on the insurance. You did buy the insurance, didn't you?

 

[sabredog]

I allow civilian ships to be armed with "defensive" weapons unless a permit is obtained for heavier armament because of where the ship operates. Defensive is defined as lasers and sand launchers. Lasers are allowed because the military classes them as "anti-missile and small craft defense weapons" so it's a loophole.

But it's a logical one since I've noticed that once I restricted lasers for anti-missile defense to being beam lasers (especially since they are shifting fire rapidly in that role) players started buying those even though they cost more and the pulse type does more damage. They do get used more often for defense, too, since players don't like getting lots of holes in their ships and if they think they are going someplace they'll need good weapons for they find a way to get missile racks...

"Offensive" is anything from a missile rack on up, and the missiles are about all you'll get to mount on a non-paramilitary ship like a Free Trader. And you're routes are probably going to have to be through nasty places but money can help grease the wheels for determined players. But a lot of places turn a not quite blind, but only more curious eye to missile racks in the area the players tend to play in: it's like having an assault rifle in your truck's gunrack instead of a hunting rifle - not illegal in some places but depending on the neighborhood it might alarm the horses.

Anything bigger than that can be on a privateer or corporate security escort but is limited to fusion gun turrets.

Bigger than that and you have to join the military and see the universe.

 

[rancke]

British East Indiaman were almost as heavily armed as 64 gun 3rd rate ships of the line during the 18th and early 19th centuries.

I believe that's a bit of an exaggeration. IIRC, East Indiamen only had guns on one deck, so they'd be almost as heavily armed as a frigate.

But they had one problem that Traveller merchants don't: they couldn't fight their guns as effectively as a man-of-war could. Their crews were much smaller, and it takes a lot of men to fire a cannon. Also, they tended to have cargo stored on the main deck, which impeded the firing. Fortunately, pirates didn't usually run to frigates, but a national frigate could be pretty confident of being able to outfight a single East Indiaman.

Whereas a 400T pirate against and an armed 400T merchant is pretty much an even fight, and no pirate ever lived to retirement age by engaging in even fights.


Hans

 

[Carlobrand]

I believe that's a bit of an exaggeration. IIRC, East Indiamen only had guns on one deck, so they'd be almost as heavily armed as a frigate.

But they had one problem that Traveller merchants don't: they couldn't fight their guns as effectively as a man-of-war could. Their crews were much smaller, and it takes a lot of men to fire a cannon. Also, they tended to have cargo stored on the main deck, which impeded the firing. Fortunately, pirates didn't usually run to frigates, but a national frigate could be pretty confident of being able to outfight a single East Indiaman.

Whereas a 400T pirate against and an armed 400T merchant is pretty much an even fight, and no pirate ever lived to retirement age by engaging in even fights.


Hans

Maybe, maybe not. Depends on how much the merchantman invested in firepower. Even winning a battle can be costly, what with the need to repair battle damage; a pirate pays that cost from his booty, but it represents an uncompensated cost to a merchantman - he's therefore more apt to avoid places where pirates are likely, and therefore to be less prepared when he finds himself confronting a pirate.

Four triple turrets cost quite a bit, and they come native to the patrol cruiser - the usual 400t pirate rolled in that game. Program selection can matter quite a bit as well, with the better combat-oriented programs costing quite a bit. And, a pirate's crew is likely to have more experienced gunners and a pilot - they do it for a living, so to speak. A well-funded pirate is likely to bring a more combat-ready ship to the fray; the merchantman may realize too late that he's cut one too many corners on his defense budget.

Under the High Guard rules, the pirate's likely to have an agility advantage and, unless that's a jump-3 merchantman, a computer advantage. That can add up to a nice edge on the combat rolls.

 

[rancke]

Whereas a 400T pirate against and an armed 400T merchant is pretty much an even fight, and no pirate ever lived to retirement age by engaging in even fights.

Maybe, maybe not. Depends on how much the merchantman invested in firepower. Even winning a battle can be costly, what with the need to repair battle damage; a pirate pays that cost from his booty, but it represents an uncompensated cost to a merchantman - he's therefore more apt to avoid places where pirates are likely, and therefore to be less prepared when he finds himself confronting a pirate.

The pirate needs to repair batlte damage too, and it comes out of his "income". It's one of the problems with the "pirates only steal cargoes" paradigm. (Other paradigms have different problems). The cost to the merchantman isn't uncompensated. He wouldn't be going to a place where he ran the risk of running into a pirate if there wasn't some profit to earn. His compensation comes from doing business.

Four triple turrets cost quite a bit, and they come native to the patrol cruiser - the usual 400t pirate rolled in that game.

You're mixing up game mechanics and "reality" here. The pirate didn't roll up his ship on a table.

Program selection can matter quite a bit as well, with the better combat-oriented programs costing quite a bit. And, a pirate's crew is likely to have more experienced gunners and a pilot - they do it for a living, so to speak.

That's possible, but only possible. The pirate is never able to know for sure how able his prospective victim is to use his guns until he receives the first return salvo.

A well-funded pirate is likely to bring a more combat-ready ship to the fray; the merchantman may realize too late that he's cut one too many corners on his defense budget.

Likely, yes. Certain, no. PC-crewed merchantmen, for example, tend to be quite tough.

Under the High Guard rules, the pirate's likely to have an agility advantage and, unless that's a jump-3 merchantman, a computer advantage. That can add up to a nice edge on the combat rolls.

That one I'll grant you. The dedicated pirate has a combat advantage, but he has other problems, such as being unable to visit any regular starport without risking the authorities getting really curious about how he makes enough money to service his bank payments.


Hans

 

[Carlobrand]

The pirate needs to repair batlte damage too, and it comes out of his "income".

The merchant's income is either a fee for shipping the cargo or a profit margin after buying and then selling the cargo. The pirate's income is the entire value of the cargo, less whatever discount he encounters from having to sell the stuff through middlemen and fences on the black market.

The cost to the merchantman isn't uncompensated. He wouldn't be going to a place where he ran the risk of running into a pirate if there wasn't some profit to earn. His compensation comes from doing business.

No guarantees there. A million credits plus to replace a destroyed triple turret and its weapons can eat the heck out of your profit margin and leave you with a loss for the trip. Enough of that, and even the risk-takers start wondering if the route's worth the trouble.

You're mixing up game mechanics and "reality" here. The pirate didn't roll up his ship on a table.

Nope, he's an npc - just like every other table-rolled NPC encounter in the game. Unless of course you're letting your players run a piracy encounter - in which case I'd like to know which bank is bankrolling 400-ton pirate ships.

That's possible, but only possible. The pirate is never able to know for sure how able his prospective victim is to use his guns until he receives the first return salvo.

Yup. Piracy's a game of chance. Just your bad luck if the merchantman had a run of good luck and invested in the best available combat software - and honestly, that kind's more likely to take his chances in a high-risk port anyway. On the other hand, the desperate out-on-his-luck kind of merchantman is also more likely to gamble - and he's the one who makes you rich. The game's all about knowing when to fight and when to run.

Likely, yes. Certain, no. PC-crewed merchantmen, for example, tend to be quite tough.

Very true. Adventurers are a positive bane to law-deriding pirates everywhere. A pox on them.

That one I'll grant you. The dedicated pirate has a combat advantage, but he has other problems, such as being unable to visit any regular starport without risking the authorities getting really curious about how he makes enough money to service his bank payments.

Bank payments?? What bank payments? What kind of a bank makes a 40-year multi-million dollar loan loan to a lawbreaker whose sole intent is to put his ship in harm's way for his own personal profit? And what lawbreaker receiving such a loan would actually turn around and buy a ship with it, when he could steal one by bribing its crew with only a fraction of that cash? We's talkin' cut-throats and ne'er-do-wells here.

My guess has always been that most of these are patrol ships that were stolen by their crews or are being operated clandestinely by desperate or corrupt planetary governments trying to bring goods and cash to impoverished worlds off the usual trade routes, or Vargr ships gone a-viking into Imperial territory. If they're stolen, then they're operating the same way pirates operated in the bad-ol' days - they're operating out of corrupt ports with no real law, where the money they bring and the bribes they pay count for more than where it came from.

 

[rancke]

The merchant's income is either a fee for shipping the cargo or a profit margin after buying and then selling the cargo. The pirate's income is the entire value of the cargo, less whatever discount he encounters from having to sell the stuff through middlemen and fences on the black market.

And that's not very much. Fences usually pay 10% for stolen stuff, 20% for the really good stuff. At least that's what several different crime fiction writers tell me.

You're mixing up game mechanics and "reality" here. The pirate didn't roll up his ship on a table.

Nope, he's an npc - just like every other table-rolled NPC encounter in the game.

The operative word is 'character'. Someone every bit as complicated as any historical character and subject to the same reality as anyone else in the universe.

Bank payments?? What bank payments? What kind of a bank makes a 40-year multi-million dollar loan loan to a lawbreaker whose sole intent is to put his ship in harm's way for his own personal profit? And what lawbreaker receiving such a loan would actually turn around and buy a ship with it, when he could steal one by bribing its crew with only a fraction of that cash? We's talkin' cut-throats and ne'er-do-wells here.

Which is why the authorities might be stirred to make enquiries when they are visited by a ship that would be very hard pressed to earn a living in an honest manner. At the very least they'll be around to pocket a fat bribe. If the pirate is unlucky a visiting patrol ship will be a lot more inquisitive.

My guess has always been that most of these are patrol ships that were stolen by their crews or are being operated clandestinely by desperate or corrupt planetary governments trying to bring goods and cash to impoverished worlds off the usual trade routes, or Vargr ships gone a-viking into Imperial territory. If they're stolen, then they're operating the same way pirates operated in the bad-ol' days - they're operating out of corrupt ports with no real law, where the money they bring and the bribes they pay count for more than where it came from.

In other words, they can't visit ordinary starports and are tied by logistical problems to those corrupt ports.


Hans

 

[Gray Pennell]

Pirates historically ply waters/space that are on wealthy lanes on the edge of patroled space at key choke points with safe havens near by. Lets take these one at a time. Wealthy lanes in the case of the West Indies this was the Spanish Gold, Rum and Slave routes in Eest Indies it was spice and other goods. The West Indies though patrolled by fleets was large and the number of shipments were high so their were often not enough ships to convoy every shipment or to guard every ship. The Spanish had gold fleets to try and reduce damage. The East India had the East India company running convoys. Pirates would pick off the stragglers and the ships not assigned to the convoys. Choke points are also key. In West Indies there are only about 4 straights to get out of the Caribbean Sea, East India the Malacca Straight was a major choke point along with the horn of Africa, and the Straights of Gibraltar. At everyone of this choke points at one time or another there have been pirate havens: Barbarie Coast, Madagascar, The Bahamas, and if my memory is correct Medan for Malacca straights. Each of these were home to dozes of pirates led by one or more Pirate Princes.

Moving to modern times all of these apply to Solomali Pirates. Here the pirates are at a choke point on a major trade route with access to a safe haven. They take advantage of the chaos in the Middle East and its taken years for the world navies to get together to stop it.

Lets move into the Imperuim. I play classic so I ll give you my take where you will find pirate activity. The most obvious is Corridor Sector as pirates attack trade between the Deneb Domain and the Core then run into the Varga Expanse to hide from the Fleets. This would be the great pirate campaign with convoy fleets, pirates of all kinds, and pirate hunters. Next comes my favorite area the Five Sisters and District 268. Here trade between the Darrian and other frontier people flow into the Imperuim. The Great choke points being Talos and Debarre Mains. Of these the Debarre has the strongest naval presence due to the Sword Worlds so the big pirate area would be the Talos main.

As for ship size and defense the Corridor would have the bigger ships formed up in great convoys so that stragglers or those who couldnt afford the convoys would get tagged. Most of the merchants would be unarmed settling for the defense of the convoy unless they are risk takers running the corridor on their own. In the other area trade isnt as well established so your most likely find the armed merchants. They cant count on the Navies: the 208th is watching the frontier and the Sword Worlds the same with the 100th fleet in Glisten watching the other end for Sword World actives. The pirates in the Corridor area will likely be large Varga raiders with a few hanger ons. In the other your talking about small ships operating as raiding fleets. Also armed merchants maybe be merchant princes one way and pirates the other. On the Talos main the safe haven would be Trexalon with their anti Imperuim attitude.

You can study other areas to find where pirates would be. The Jump 5 route across the Rift?, the area between Aslan and Solomani space. There might be dozens of locations to have good pirate campaigns. We often wonder what all the Imperuim Fleets are doing well running convoys and putting down pirate princes might just be a big part of their activities. When war breaks outs the pirates come out. When peace time occurs the pirates are reduced but tie up fleets this in turn might lead to more larger conflicts as powers grow bold in the vacuum left by fleets chasing pirates.

So pirates do exist IMTU but not because of weapons or fleets but for geopolitical reasons that have been around for thousands of years.

 

[mike wightman]

IMTU piracy has several reasons for occurring:

megacorp sponsored trade war

rival duchies settling their differences

rival worlds settling their differences

rival interstellar state sponsored piracy

ethically challenged merchants acting on opportunity

Remember - you can serve 7 terms in the pirate career, there is a retirement package, there are purpose built corsair ships - oh, and Int is the most important stat for survival and promotion (if you can win the early fist fights )

 

[rancke]

No one is denying that pirates exist in the Traveller Universe. I'm sorry for touching off another round of pirate discussions and would like to try to smother it in its infancy, if I may be allowed to mix metaphors.

The original question was, IIRC, if, given that pirates exists, it is reasonable that civilian ships are allowed to arm themselves. I think it is.


Hans

 

[Gray Pennell]

yea Hans I tried to get back to that in the end. Short answer in the Corridor probably not, you run with the convoys on the Talos main you do or your pirate meat. It just depends on your location relative to a fleet and if the fleet is taking care of the pirates or doing other things.

 

[Ran Targas]

IMTU merchies are limited to single turrets and the responsibility for defense falls squarely on the shoulders of the Imperium and the local governments. As the vast majority of merchants never travel outside the vicinity of populated worlds, to and from a jump beacon, this is a much easier proposition than trying to police entire systems. It's the stray merchant who wanders off the beaten path that runs a risk, but they're never up to any good anyway

And don't forget about those pesky insurance companies that back shipping companies; they might frown on heavily armed merchants with poorly trained crewmen (in comparison) playing "Navy". A merchant is not a warship; low manueverability and bad firing arcs. Might be too big a risk to back, leaving the ship owner holding the bag.