Scammers call claiming to be from the local Department of Public Safety (DPS) or a similar organization in your state.
They are looking for donations and what they offer instead is a decal or sticker with the DPS logo. The stickers are to be placed beside the back license plate and are meant to waive your next traffic ticket, as an appreciation token for your donation.
How to avoid: if you get a traffic ticket you broke the law, so you will pay for that. There is no such thing as DPS “life saver” stickers.