If you're on probation, and have to submit urine samples to convince the court you're keeping to the terms of that probation, handing over cold water instead of piss is probably a stupid idea.
Didn't stop Meek Mill doing it though:
Mill failed check into court every 60 days to have his travel approved, while a urine sample he submitted was in fact reported to be cold water, although Mill says he did not tamper with it.Yeah. Taking it straight from the tap doesn't make it any better, Meek. The judge isn't annoyed that she thought you'd put it through a Britta Filter.