> If an AWS employee commits fraud as part of his employment which results in a financial loss for a client, the employee will be criminally liable, but amazon will be financially liable to the client. Why would it be different for a police department?

It will be different because of QI: the reason Amazon will be legally liable is that the individual employee is legally liable in the first instance, and Amazon is jointly and severally liable for the employee’s liability (and a much more attractive litigation target, because you can’t squeeze blood from a stone but you can squeeze money from a trillion dollar corporation) because of the legal principal of respondeat superior.