How do I keep spellcasters from casting while in jail?

Question

Interesting situation came up in my session. The players captured a wizard NPC and put him in jail. Then came a long discussion about what measures needed to be taken in order to prevent said wizard from using spells to force his way out.

Basic measures like removing a spell book, holy/arcane focus, and spell components would prevent use of any spells with a material component. A gag would stop verbal spells and being bound would stop somatic spells. However this is an unsustainable level of treatment for a jail for more than a day or so since it would have to be applied to ALL prisoners since there is no easy way to tell who can cast and who can't.

Preventing a long rest would severely handicap most casters in that it would prevent recovery of spell slots/sorcery points, although a warlock wouldn't be affected. Seems like a basic precaution to not allow prisoners long periods of rest. But this doesn't affect unused spell slots and no character class, from what I can tell, "loses" spells if they don't perform some sort of ritual each day (they just can't change their prepared spells if applicable), even the wizard. So unless a caster is tapped out on spell slots/sorcery points before being jailed, they would always retain what they have left even if denied a long rest (and would still have cantrips).

So, apart from being tightly bound, gagged, and stripped, are there any ways to prevent casting that I'm missing?

There are plenty of verbal only spells that would be useful in a jail environment (Command, Knock, Misty Step) so really, how are casters supposed to be locked up other than some sort of dedicated magicked prison (assuming you could even transport them there)? Just taking out the gag to feed them opens up the possibility of a spell being cast. I don't want my characters to have to be treated like this if they get jailed, but it seems like in a world of scarse magic items but numerous magic wielding people, anyone not KNOWN to be non-magic using would be treated like Hannibal Lecter or put in an Arkham Asylum type specialty prison (bad example, folks escape from there all the time! Maybe the one from Harry Potter).

My homebrew solution is to have the higher levels of exhaustion stop casting. This way someone who has been in a jail for more than a few days can't cast due to poor conditions, poor food, etc. But they can still move around a bit and talk, so there are role playing possibilities (barter for more food, become prison kingpin to get better treatment, bribe a guard, etc). When captured maybe casters could be bound and gagged, but it wouldn't be necessary for long term imprisonment.

I'm using the basic vanilla forgotten realms setting with the suggested "low magic item availability" from the 5e PHB and DMG. Judging from the published campaigns I've read (Phandelin and Horde) there does not seem to be common availability of magical effects and devices. Party level is 5-9th level.

The answers to the previous setting-free question How could towns restrain a magic user? has plenty of useful "soft" suggestions like archers on the roof. But I would like some 5e and Forgotten Realms-specific techniques.

Answer 1

There are a number of different strategies one can take (besides the possibly obvious: remove material spell components/focuses/holy symbols/etc.):

1. Make the jail special
   

• Suppress sound (e.g., permanent or ongoing silence) to eliminate verbal spell components

• Suppress light so that the spell caster cannot, for example, target individuals or locations via line-of-sight (e.g., use illusions over doors or windows to block line of sight).

• Suppress divination (e.g., permanent or ongoing nondetection) so that the spell caster’s buddies cannot scry in order to pop in via, say, teleport, and rescue them.

• The jail is built in an area that "naturally" suppresses, hampers or distorts magic.

• The jail is constructed using permanent or ongoing anti-magic spells

NOTE: Following up on one of SevenSidedDie’s comments on the original question, spell caster-proof jails may be rare enough and expensive enough things, that one would not expect small towns, or even necessarily any particular city to have the capacity to hold a spell caster (although this will depend somewhat on how common spell casters are in the campaign setting, for example, if every small town has a few high level casters, then these kinds of jail enhancements might be common). This kind of scarcity might make the possession of a spell caster-proof jail a special resource for a region, or even between nations/principalities/city states/etc. where extradition treaties, rendition treaties, or even trade treaties are negotiated around arranging the incarceration of a spell caster (imagine a side narrative about arranging the transfer of a incarcerated spell caster: fun!).

2. Alter the incarcerated spell caster
   

• Magically compel the spell caster not to use spells while incarcerated in jail (e.g., a geas, some really nasty custom curse, mark of justice, etc.).

• Make the spell caster wear some difficult to remove (probably homebrew) magic item that suppresses somatic movements, sounds, or even magic.

• Tag the incarcerated caster with difficult to remove tracking and summoning magic, and make them aware that there will be sanctions for jailbreaks.
  

• Place the spell caster in some kind of suspended animation (e.g., the vanish sink spell of 1st edition AD&D).

• Drug the spell caster so that they are incapable of casting (per orlp’s excellent comment).

3. Have the jail include guardians who are practiced at containing spell casters.
   

• Abjurationist wardens

• Mage-slayer wardens (perhaps equipped for and specializing in non-lethal combat and restraint)

• Wardens equipped with anti-magic devices

• Wardens that are magic-suppressing, magic resistant, or magic immune monsters or constructs.

4. Make compelling appeals to the incarcerated spell caster’s reason, morality or emotions

• Threaten the spell caster’s familiar, family, colleagues, or benefactor with sanctions (e.g., your family pays a huge fine if you jail break; your familiar will be destroyed if you jail break; your teacher will be stripped of standing in the college of magic if vouchsafed spell casting students jail break; your first born child will receive the spell caster’s sentence if they jail break; etc.).

• Appeal to the sanctity of law (if that is something that the spell caster cares about).

• Escalate the legal threats against the spell caster by compounding an original crime with a jail break (e.g., the punishment originally was 6 weeks in the clink and a small fine, now it is the amputation of your right hand).

• Make plea deals, so that publicly the spell caster is seen as punished, but the powers that be arrange to trade benefit for leniency in actual sentencing.

Answer 2

Going in a slightly different direction: don't go overboard. Most small-time prisons probably have a few minor defenses against spellcasters. They'll have their stuff taken, they'll be behind iron bars, if the jailor expects them to be spellcasters he´ll wear earplugs and hang the key on a 20 pound weight so it can't be Mage Handed and it´ll probably be dark, which makes vision targeting hard. Other than that; maybe a double set of doors with different keys, so that a single charm won't help, and a number of guards with orders to kill anyone who tries anything funny.

If you go above and beyond this kind of thing for a general kind of prison, then you are basically unfairly targeting wizards. Most Wizards, especially the kind that you'd find in a low-level prison, will be contained by the above. If they try anything funny, they get stabbed to death by the guards. Most would probably not even try to escape. For every guard you charm, there's 5 more with pointy weapons.

Remember: many characters have a glib tongue and can talk their way out of a prison. We don't go around asking "how do you keep a silver tongued rogue in prison?". We don't ask "How do you keep a barbarian who can bend the bars in prison?", even though they probably can when in a Rage.

If the wizard is high level and in a small-town prison he will be able to escape. So will any other high level character put in that situation; it's not a Wizard problem as much as it's a high level character vs low level challenge problem.

Now of course when it comes to special anti-powerful-wizard-prisons, you can go all out, but those are fantastical locations, not simple buildings designed to hold not so powerful people.

Answer 3

Don't be shocked but you asked for a 5e specific answer and not a general answer.

You take the wizard's tongue. The wizard will then be unable to cast any spell with a verbal components. I believe this is all 5e spells. If ever there are any somatic only spells you remove the hands as well. It is preferable to keep the hands if possible because you can then use the wizard as labor. You could rule that only the removal of some fingers is enough to ruin the somatic component of a spell.

When you wish to release the Wizard you use a Restoration spell to restore the Wizard's missing body parts, and fine him the cost of the spell or spells.

Short of death or magical means mutilation is the only mundane way to ensure a wizard can not cast spells in the long term under the 5e rules.

Update There are four somatic only spells.

Beast Sense, Counterspell, Mislead, True Strike.

Of these Mislead is the serious threat and is able to be cast by a wizard.

You become invisible at the same time that an illusory double of you appears where you are standing. The double lasts for the duration, but the invisibility ends if you attack or cast a spell.

Likely because of this spell both of the wizard hands would be removed or the wizard is bound in a way to prevent the use of somatic gestures. This would last until the authorities are satisfied that the Wizard has not prepared Mislead.

Answer 4

Honestly, this question is well answered, but there is an additional security measure that can be added to any implementation seen here.

Lock him in some restrictive 'heavy armor'. Unless he got the feats for that reason, he can't cast in that armor.

Answer 5

Invent something.

It can be as simple as "iron shackles and collars block magic".

If your wrists are surrounded with an unbroken ring of mundane iron, you cannot do somatic magic. It just doesn't work -- the iron "grounds" it.

If your neck is surrounded with an unbroken ring of mundane iron, you cannot do verbal magic. It just doesn't work -- the iron "grounds" it.

Break either -- even a crack -- and you can do magic.

This applies to all forms of magic that require V and S components (divine and arcane).

Then block access to material components (and foci).

This makes imprisoning even a wizard possible. No requirements to be paranoid, extra torture, anti magic cells, etc: just iron.

All prisoners can be shackled that way, as can slaves, so they don't need to know if someone is a wizard or spellcaster before imprisoning them. This also opens up a way for a spellcaster prisoner to break free -- crack their shackles or their collar -- without it being automatic.

Finally, placing such restraints on someone basically require they be helpless, so it doesn't provide an easy way to nullify spellcasters "in combat".

And for extra fun, fake collars and shackles made of something besides iron can be used to "pretend" to be a prisoner or slave, but still be able to use magic.

This kind of "change" can be injected even into relatively heavily designed worlds without changing much of notice. A high security dungeon for wizards would still want anti-magic, due to the ability to remove said shackles, so even anti-magic dungeons could be explained away. Meanwhile, a hedge wizard can be put in jail without having to go crazy with precautions, or cutting off their hands/tongue.

Answer 6

Your methods of suppressing spellcasting at a basic level involve denying your prisoner access to spell components. Components come in three varieties: Verbal, Material, and Somatic.

To cast a spell with a verbal component, the prisoner must be able to speak loudly. A simple gag or magical silence will do the trick, causing all spells requiring verbal components to be uncastable.

Material components are used in seemingly few spells in 5th Edition; however, they do exist. Denying a wizard access to her spell component pouch and arcane focus effectively blocks the casting of all spells that require material components.

Finally, somatic components require freedom of movement. Cuffs, shackles, or any other means of preventing the caster from moving freely blocks all spells requiring somatic components from being cast.

Finally, any well-equipped prison in a magic-is-pretty-common campaign will also take appropriate safeguards from external intrusion, including the use of the 8th-level Antimagic Field spell.

Cheers!

---

As a point of inspiration, here is something we had in our campaign that you might find useful to consider.

We played for some time out of the exquisite Ptolus campaign setting by Monte Cook. Within the metropolitan city of Ptolus is Mahdoth's Asylum, a sanctuary for the magically insane. This asylum is designed to make spellcasters comfortable and keep them from society at large, but is not meant to be a punishment.

The entire subterranean living area is guarded with an Antimagic Field. In addition, the proprietor is an "Ocular Tyrant"--Monte Cook's variant on the Beholder--with a powerful antimagic ray in his primary eye. The combination of the anti-magic field and the powerful anti-magic guardian made for a prison where the inmates could live in relative comfort and yet be denied access to spells.

Answer 7

I prefer the "special tea" approach, taken from the Wheel of Time series.

An herbal tea made from commonly available plants which, when consumed, makes a spellcaster unable to cast spells for a certain period of time. The brew can be prepared by any herbalist, but tastes strongly of anise, has a medicinal/metallic aftertaste and it burns slightly like too much pepper, making it all but impossible to mask without magic.

Since you're drinking a lot of it, you get no save (a small amount or weak dose would probably grant a save, DC 10-15). I also make it detectable by detect poison and the like, and curable by neutralize poison. Players of dwarves who point out their natural resistance to poison earn a second dose from the guards. I usually go for 25 to 48 hours duration.

I like it because it means the players have to do more than break their bonds and find their equipment to magically escape, and because it feels more fallible than, say, antimagic handcuffs, but actually is quite effective. It means their confinement is more complicated than a prison door, and it means they won't try to steal your magical handcuffs. It's also nice that you can't visibly tell when someone is barred from casting. Last time I used it, I made it a greenish brown porridge of roots and herbs offically called "magebane," but everybody called "demon dung" or "dragon dung" because of the look and bad taste. Getting a visceral reaction from your players is fun.

The only time it doesn't work well is when you have Warforged.

Answer 8

Here's how I deal with this: let the character escape. And now he's guilty of something far worse than whatever minor crime got him locked up originally. Jailbreak is a felony, maybe even a capital offense. He's suddenly notorious; his name is known to every guard, he's that Scofflaw, that That Jailbreak Guy, and no mere petty criminal. Word spreads and the population fears him because he's a Threat To Society, Unmutual, whatever label you like. Wanted posters go up everywhere. Only other criminals will deal with him. And if a few guards run across him and he happens to oops, die in the intervening attempt at arrest... the legal system will turn a blind eye to it because you just can't have people escaping jails all the time, so we'll just use death as a prison. Knock those chains, buddy.

If this is likely to be a thing the players run into, I'd let them hear some legends of this happening, early on. A "Wanted dead or alive" poster in an Inn and a Innkeeper who knows the story of Blake the Infamous... if the players don't take the hint, one of the characters will eventually serve as an object lesson to the rest.

It's just sense. Prisons, especially in small towns, simply don't have the economic resources to handle unusual cases like mages. They might take a few simple precautions, but even the previously stated idea of putting someone in armor all the time, while brilliant, is expensive (and they have to be let out of the armor eventually.) Societal pressure is cheaper and very effective.

Answer 9

Frankly, in the world that 5e has set up it would be difficult at best if you are not using the standard methods of restraining.

Outside of an elite prison built for mages, guards that guard them would need earplugs to avoid any enchantment, and some form of hand/finger restriction would be necessary (manacled to their back with gauntlets that restrict any finger movement). Only the best trained guards in the village or trained animals should guard them (if druids, nix the animals). Trade guards out as frequently as possible to ensure no complacency. Most of the time a mage is unlikely to have Knock memorized, so it is unlikely to be used. Obviously those performing B&E are exceptions as would likely be an Arcane Trickster.

They would, of course, need to be stripped of gear and given prison rags to wear.

Ultimately, you have most of the ways listed above, but guard quality and restricting their actions when not actively working as slave labor (common among prisoners) would do the trick.

Treat them very badly as well... The paranoid are going to ensure they never get a short rest (if warlocks are common), let alone a long rest. They should be performing demanding physical labor to keep them exhausted, sure. Slap them around a bit. It's a harsh world and those worried about spell casters that actually know about what they can do would take serious precautions.

It also depends on how much or how little you want to make restricting movements to break somatic components. Simply tying hands behind the back with rope may be enough in most cases.

In FR, it would be easier to find a spellcaster to restrict the inmate than a magic item, so using spell casters to stop them would be helpful, but using a high level caster to stop an entire prison's worth of inmates would be a bit ridiculous.

As a side note, Forest Gnomes are resistant to most of the spells that might cause a guard a direct problem, then they just have to be vigilant.

Understand that when it comes down to it, they can't stop everything and eventually a caster is likely to find a way to escape if they had any memorized/known spells that might help at all and they are tenacious about it. It makes the game more dynamic and interesting when a dedicated criminal can get away with an escape.

In settings that are a bit gritty or the populace is particularly afraid of casters, cutting out the tongue or severely disfiguring the tongue/mouth would be used for serious crimes (how serious depends on how much they fear magic). It is unlikely that they would care enough to actually worry about how it could be restored after the sentence is over... more of a permanent price to pay for misusing mystic arts (or using them at all, perhaps).

I don't think that cutting off hands is realistic for spell-casting in all but the most xenophobic of cultures. Almost all spells are verbal.

Make the punishment fit the city. Small towns will be less prepared. More xenophobic ones will be more likely to use dismemberment, death, or other extremes to get their point and punishment across. Larger towns and more egalitarian towns will be more likely to use humane and/or magical methods to temporarily restrain them, and if the world has some of the worst criminals that use magic, and a way to contain them, that should be considered in extreme cases.

The last method is a very quick trial leading to execution for misuse of magic.

Answer 10

I would go the opposite route to most of these answers (if possible): Instead of making sure a spellcaster with spell slots remaining cannot use them, I would make sure the spellcaster does not have any spell slots remaining (then prevent long rests as you indicated in your question):

1. Gather enough/high enough level guards/casters that the character would not be able to overcome even with all of their spell slots
2. Have a Paladin cast "Zone of Truth"

3. Ask them how many spells they can cast of each level before their next long rest (threatening them with removal of hands/tongue if they refuse to answer—or any other answer to this question—death, gagging + tying hands, herbal tea, whatever). Once they answer, you know its true, and proceed to next step. If they don't answer, follow through on your threat (of whatever severity you chose).

   • For PC wizards/spellcasters who have been captured, making and following through on a severe threat may feel pretty bad for the player. Stick to lesser threats if you anticipate players may ever end up in this situation. NPCs can always still choose to use up their spell slots: it would make for a much more comfortable jail stay than even the least of the other answers.
4. Force them to use all of their remaining spell slots in a verifiable way, while monitoring them closely for shenanigans
5. For extra confirmation, cast Zone of Truth again and ask them if they have any remaining spell slots. Repeat 4 and 5 until you get a verifiable "No"
6. Disband the high level guards
7. Prevent them from taking a long rest for the remainder of their stay
8. Rest easy

One advantage of this approach is that it more closely parallels how you'd treat other classes: Would you take a fighter's weapons away, or would you let him keep them while tying his hands behind his back for the entire stay? Would you take a rogue's equipment away, or would you leave him his equipment and glue his fingers together?

The sensible answer in all cases is to take away the threat, not try to make it unusable in some way by treating the prisoner unnecessarily cruelly.

The other advantage is that if a traitorous guard wants to help the spellcaster escape by restoring his spellcasting ability, it's not enough to remove a gag or other piece of equipment: they need to help him get a long rest (which takes much longer and should be easy to prevent), so it is also more secure.

Answer 11

It depends on what type of spells you want them to stop casting, but there are a few options

Put your jail in a demiplane and prevent "Extradimensional Movement"

First have a sufficiently high level caster create a Demiplane and build your jail in it. Place all of your prisoners who can cast spells into this Demiplane prison.

The Dimensional Shackles magic item will prevent the bound mage from:

using any method of extradimensional movement, including teleportation or travel to a different plane of existence. Though they don't prevent the creature from passing through an interdimensional portal.

There are some potential logistical issues here (like your prisoners not suffocating) but these could be mitigated. One potential mitigation is the following:

• Give all of your prisoners and a guard mage Caps of Water Breathing
• Have the Guard Mage cast Create Food and Water to create much food
• Cast Create or Destroy Water to fill the chamber entirely with water (using the rain option), and occasionally cast it in a container in the chamber to recycle the water (destroying and then recreating the 10 gallons of water)

Create a the prison in a permanent Antimagic field

Antimagic fields prevent magic from working inside them. Simply have the prison be constructed inside one of those and poof, no spellcaster can cast spell in them.

Create a magic item which can spam counterspell

There is precedent in

Dungeon of the Mad Mage (see Halaster's Tower)

for an item which can spam counterspell when a creature is near it.

Put them in a suit of heavy armour

The majority of wizards do not have proficiency in Heavy Armour and thus are unable to cast spells while in Heavy Armour.

Feeblemind the caster

If you aren't particularly concerned for the safety of the prisoner then just cast feeblemind on them. The feeblemind spell prevents the caster from being able to cast spells (assuming they fail their save). If the caster of the feeblemind is powerful enough it would be possible to practically guarantee low level caster's fail their save.

If the caster dies because of it, just cast revivify on them to bring them back. The feeblemind condition isn't ended by death...only by making a save, Heal, Greater Restoration or Wish!

Answer 12

Medieval societies didn't really build prisons for criminals.

In medieval Europe, imprisonment was almost never used as a criminal punishment; generally, it was reserved for noblemen and noble women who had been captured and were being held hostage until their ransoms were paid, or as a temporary measure to hold a criminal until their execution can be performed.

Holding someone in prison is expensive, since you need to pay for their food and water, the guards watching over them, and similar expenses, without getting any economic benefit out of it.

For criminal punishment, you'd usually see penalties like fines or corporal punishment for the more minor offences, exile for more serious offences, and execution for the most serious offences.

Jails (along with organised and dedicated law enforcement officers) are a thing that was more or less invented during the early Victorian era as the population of cities exploded.

Answer 13

Well, if you don't want to make up a magic item that has a continuous effect of stripping spell slots (manacles of forgetfulness) or keeps them asleep, stunned, paralyzed or otherwise incapacitated; you can blindfold them and use sovereign glue on their bare feet and the cell floor. Without using any magical items and not doing permanent damage to people like cutting out tongues and fingers, your best bet would be to have them hooded, as it's hard to target something/one or teleport somewhere if you can't see, and gagged while making it known that when the gag comes out for feeding time, there is someone posed with an axe to strike if they even start making a sound. They would also have to be manacled so that their hands are either in fists or otherwise unable to move arms and fingers. If your party is really creative, you might want to have their feet bound as well to prevent magic movements with toes. Picture an old Hagar the Horrible cartoon where he's chained spread eagle to a wall and add a hood and gag. I suppose if you want to avoid the fuss, just make the cell in a naturally/unnaturally occurring dead zone for magic, maybe a permanent antimagic field spell is cast on the dungeon or the cells are surrounded by strange glowing rocks that fell from the heavens or up from the underdark that dampen magical energies. Depends what works best for you. These aren't the only solutions, just what came to mind.