This is one of the main reasons I have a cam in the front and back of my vehicle. It' records at all angles. It's not just for cops but that's one reason I have them installed. I don't trust cops.
Here is a solution: Purchase a Car DashBoard Video Camera Vehicle Video Accident Recorder.
This Dashboard Video Camera has the best rating among people who bought it recently:
HD CAR DVR Rear View Mirror G SENSOR 32GB SD card accident camera video recorder HDVR-150
Buy on Amazon.com Price: $169.00
Stealth design: clip on original rear mirror (with cable neatly tucked, you would not know it's there) / Super easy installation: no windshield mount required.
High resolution: up to 1280*720 (HD 720P) / Built-in hidden screen to the mirror: 2.4"TFT LCD monitor on or off (Instant playback, instant real time viewing) / Built-in wide angle lens: Diagonal view angle is 120 degrees.
Automatic on / off: when engine starts / off (depends on power of cigarette plug) / Loop recording: worry free for storage space, auto replace the oldest file.
Audio: Synchronized video/audio recording / Low illumination image sensor / Lens adjustable 360 degree, fits left or right hand drive / Support digital camera function / No recording gap between file clips / Keep recording for 10 more seconds after power stops
Anti-Glare tinted glass / Blend in car interior design. No windshield view blocking.
G Sensor: block important files from being loop recorded / Storage: Support SD/SDHC up to 32GB / Recording time before it loops recording: 1280 x 720, 5hrs; 640 x 480, 13hrs42mins; 320x240, 38hrs52mins
First, I ordered the item on Nov 8 and Nov 12 it was in my hands. Mind you, the product comes from Taiwan. As other have said, personal note was icing on the cake. It's been 2 weeks now and the product works superbly. It does come with 32GB card and all the internal settings (Include date and time) had been pre-set correctly for me at the company. All I did was snap it on my Camry '12 rear-view mirror, hide the wires and done. Fitting for me was tight and sturdy. Cable was more then long enough to visually be out of sight through the nook and corners. I HIGHLY RECOMMEND this product. Amazed how good the video is at night even with no street lights. Directions provided are thorough and easy to follow. Great product!