03-06-2017, 04:15 PM
Legally they do have the right to detain you and search you and your bags or vehicle upon entry to the country, it's been that way for a long time this wasn't something new post 9/11. However you are not legally required to answer any questions. You are well within your rights to inform them you wish to remain silent. Of course this will cause you major delays and if you have something prohibited hidden they will probably find it anyway. I have no idea about the filming.
In your case if you think you can't control your comments, it's probably best to remain silent and let them do what they want then go on your way.