Being released under investigation means that someone is suspected of a criminal offence and that the investigation into their alleged criminal activity is ongoing. They may have been arrested, but they have not been charged, nor has their case been passed to the Crown Prosecution Service. However, they are not out of the woods, because the police are still suspicious that they might have committed a criminal offence.
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Indeed, RUI is often perceived, to the detriment of both alleged suspects and alleged victims, to be a pending tray for more complex cases, allowing overstretched detectives to tackle simpler cases with an easier prospect of conviction, which is a very unsatisfactory state of affairs.
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To paint a picture, typically what happens is that someone is interviewed under caution by the police, but there are not sufficient grounds to charge them. However, the police do not want to dismiss that person as a suspect just yet; instead, they want more time to make their inquiries, before deciding whether or not to refer the person’s case to the Crown Prosecution Service. The police therefore choose to release the person under investigation, which allows the person to leave the police station, but the police can still seize their personal property as evidence.
The person will be told about the outcome of the investigation at some point in the future. That creates a great deal of uncertainty, because they do not know if the police will eventually charge them or drop the case against them. To make matters worse, the investigation process has no maximum time limit, which is absolutely ridiculous. It means that the person could be kept waiting for weeks, months or even years before discovering their fate.
