Condemnation to Hard Labour 131Theoryand practice might also diverge in the matterof the penaltyof
vincula. Given that, as mentioned above, persons in prison were also nor-
mally shackled (unless bribes were used to avoid this,Dig. 48, 3, 8), many
referencestovincula,orvincula publica,aresimplytoimprisonment.Butitis
clearthatvinculacouldinpracticefunctionasanalternativetoprison;thisis
clearlyimplied,forinstancebyUlpian,citedabove(Dig.48,19,8,9).Being
analternativetoprison,itwasinprincipleatemporarymeasureofdetention,
appliedtofreedefendants(Dig.48,3,3).Asapenalty,beingkeptinvincula,
foreitheraspecifiedperiodorinperpetuity,wasappropriateonlyforslaves
(text to n. 8 above). It appears for instance in the Lex Metalli Vipascensis:
aslaveguiltyofstealingfromthemineistobesoldoutsidetheboundsof
theminingarea,andonconditionthatheshouldbeinperpetua vincula(in
chainsforlife)—thatis,whileinprivatepossession(FIRA^2 I,no.104,ll.25–
30).Nonetheless,heretoothetreatmentofslavesmightinfluencethatof
freeconvicts.Theimperialmandata(instructions)forbadeany(free)person
frombeingkeptinperpetuavincula(Dig.48,19,35).Caracalla,however,wrote
in214:‘‘Whatyouallegeisincredible,namelythatafreemanhasbeencon-
demnedtobekeptinchainsinperpetuity;forthisprocedurecanscarcelybe
followedevenasregards(apersonof)servilestatus’’(CJ9,47,6).Wecannot
tellwhetheritwascommoninpracticeforthisregularslavepenaltytobe
applied to free men. But even temporaryapplication ofvincula, like being
thrownintoprison(above),willhavebeenregardedasdamagingtostatus.
ThisisperfectlyclearfromUlpian’sinclusionofpersonsinchainsamongthe
categorieswhocouldclaimrestitutionbecausetheywerenotinaposition
toappearinacase.Hiswordsalsoillustrateonceagainthevarietyofagencies
whomightkeepamanunderarrest:‘‘Thoseareinthesamecategorywho
arebeingkeptunderarrestbysoldiersandstatores[militarygrooms]orby
municipalservants,ifitisprovedthattheycouldnothaveappearedfortheir
case.Forwehavedefinedthoseasbeingin vinculiswhoareboundinsucha
waythattheycannotappearinpublicwithoutindignity[sine dedecore]’’(Dig.
4,6,10).
TheNatureofOpus Publicum
Imprisonmentthereforewasnot(inprinciple)arecognisedlong-termpen-
alty, whatever might happen to individuals, sometimes even before reso-
lution of their case, like Paul, who was kept for two years in the ‘‘praeto-
rium[governor’sresidence]ofHerod’’inCaesarea(Acts23,35;24,27),orthe
people about whom thekoinon(common council of a league of cities) of