analyst
analyzer
asker
catechist
cross-interrogator
cross-questioner
detective
examinant
inquirer
inquisitionist
inquisitor
inspector
interlocutor
interpellator
interrogator
interrogatrix
interviewer
investigator
observer
opinion-sampler
poller
pollster
prober
querier
querist
questioner
questionist
quizzer
sampler
scrutineer
secret agent
tester
visitator
visitor
enquirer
cross-examiner
accountant
administrator
adviser
attorney
auditor
commissioner
consultant
coroner
instructor
juror
marshal
pathologist
practitioner
prosecutor
psychiatrist
sheriff
superintendent
supervisor
surgeon
technician
warden