blow the whistle on

Meaning

to tell people in authority about something wrong that someone is doing

Examples

1. 1A nurse blew the whistle on the hospital's poor hygiene, and inspectors arrived the next day.
2. 2It takes courage to blow the whistle on your own employer.
3. 3An accountant blew the whistle on the charity after noticing that donations were disappearing.
4. 4If you see a colleague stealing, you should blow the whistle on them.
5. 5Who blew the whistle on the factory's illegal dumping? The newspaper won't say.

Grammar

Only blow changes: blows, blowing, blew, blown. The person or organisation follows on.