There is just so much wrong with this I don't even know what to say.
One of the absolute key parts of therapeutic communication is honesty. Regardless if they are EDP or not, you NEVER lie to your patients! Your wording in this also makes me concerned that you really lack the skills to deal with psych patients, the bolded statement in particular. I strongly suggest you do research on therapeutic communication skills as they will help you communicate openly and honestly with the psych patients you encounter, while keeping them as calm as possible. Nothing positive comes from lying to patients.
Unless the patient is super combative, the cop should ride out of view of the patient, this will help keep the situation calm and in control. Restraints should be a last resort and not just because they get "rowdy." There has to be a direct threat to you or the patient to place someone in restraints. They are indicated at times, but should be checked every 15 minutes and on long transports, you should change the position of the restraints at least every hour. Restraints have some very serious consequences if they are used improperly and should not be taken lightly.