If someone says ‘So ans So sold me drugs/robbed me/raped me/threatened to kill me/etc’ and there is no other evidence (no other witnesses, no physical evidence, no video/audio, etc) to support the assertion of a crime other than one person’s hearsay, is that sufficient evidence to arrest and charge someone, or is that alone not enough? Or does it depend on the crime?
I’m under the impression it starts with an investigation where the person being investigated is free to leave. After that comes the arrest (you are no longer free to leave after that), after that comes the conviction. The process could break down at any step.
DAs and prosecutors want to win as many cases as possible, so I assume most would not take on a case with no evidence other than one person saying a crime happened. But I have no idea about the motives of police, if police are affected by having arrests that do not result in prosecutions and as a result if they are motivated to arrest as many people as possible irrelevant of whether it results in a conviction, or if they are motivated to only arrest when a conviction is likely, or it is not a factor or what.