I expect that they intimated that he wouldn’t be released in a timely fashion if he did not co-operate. LEOs are trained in intimidation, trained to make you give up your legal rights. The deck was stacked against him.
Having never been held in custody, I don’t really know what I’d do. The cops have lots of experience in intimidation and lots of powerful tools of oppression at their disposal. I have little to no experience at opposing them. So while in my fantasy world, I’d do everything the ACLU tells you to do, I also know that without practice in advance under similar conditions it can be hard to do what you think you’d do when it happens IRL.
