investigation
noun
ɪnˌvestɪˈɡeɪʃn 
ɪnˌvestɪˈɡeɪʃn 
1 an official examination of the facts about a situation, crime, etca criminal/murder/police investigationShe is still under investigation.investigation into something The police have completed their investigations into the accident.2 investigation (into something) a scientific or academic examination of the facts of a subject or problemSynonym
enquiryan investigation into the spending habits of teenagers
Usage note: CrimeCommitting a crimecommit a crime/a murder/a violent assault/a brutal killing/an armed robbery/fraudbe involved in terrorism/a suspected arson attack/people smuggling/human traffickingengage/participate in criminal activity/illegal practices/acts of mindless vandalismsteal somebody's wallet/purse/(British English) mobile phone/(North American English) cell phonerob a bank/a person/a touristbreak into/(British English) burgle/(North American English) burglarize a house/a home/an apartmenthijack a plane/ship/bussmuggle drugs/weapons/arms/immigrantslaunder drug money (through something)forge documents/certificates/passportstake/accept/pay somebody/offer (somebody) a briberun a phishing/an email/an Internet scamFighting crimecombat/fight crime/terrorism/corruption/drug traffickingprevent/stop credit-card fraud/child abuse/software piracydeter/stop criminals/burglars/thieves/shoplifters/vandalsreduce/tackle/crack down on knife/gun/violent/street crime; (especially British English) antisocial behaviourfoil a bank raid/a terrorist plothelp/support/protect the victims of crimeInvestigating crimereport a crime/a theft/a rape/an attack/(especially British English) an incident to the policewitness the crime/attack/murder/incidentinvestigate a murder/(especially North American English) a homicide/a burglary/a robbery/the alleged incidentconduct/launch/pursue an investigation (into…); (especially British English) a police/murder inquiryinvestigate/reopen a criminal/murder caseexamine/investigate/find fingerprints at the crime scene/the scene of crimecollect/gather forensic evidenceuncover new evidence/a fraud/a scam/a plot/a conspiracy/political corruption/a cache of weaponsdescribe/identify a suspect/the culprit/the perpetrator/the assailant/the attackerquestion/interrogate a suspect/witnesssolve/crack the case more collocations at justice