Most of them aren't hardened criminals. Lycion is pretty much mentally ill and Fleki is implied by her 'first death' thing to have been in some accident involving spores that got her addicted. Pattadol is just a conscripted teenager.
Cithis, or Sisuhime I guess (I really can't get used to the idea of an elf having a Japanese name), is the one that really seems like she was a proper criminal. I kinda wonder what her circumstances are, like, WHY she's doing fraud.