The　Chinese　government　is　dedicated　to　enhancing　the　level　of　informatization　in　administrative　law　enforcement　to　ensure　fairness　and　increase　credibility.Currently,law　enforcement　has　exposed　such　problems　as　insufficient　force,difficulties　in　collecting　evidence,and　low　evidential　power.These　problems　contradict　the　principles　of　rule　of　law　and　standardization.Many　local　governments　have　implemented　advanced　information　technologies　for　urban　administration　and　law　enforcement,including　big　data,artificial　intelligence,and　IoT.Among　these　technologies,IoT　is　the　core　communication　infrastructure　for　innovative　law　enforcement　platforms.However,traditional　video　communications　rely　on　batteries　or　dedicated　power　sources,leading　to　maintenance　challenges　and　high　power　consumption.In　this　paper,we　propose　AT-Eye,a　new　video　communication　paradigm　for　all-time　law　enforcement　video　monitoring,which　is　battery-free　and　high-throughput.The　key　enabler　of　AT-Eye　is　ambient　backscatter　technology,which　enables　energy　harvesting　and　video　communication　simultaneously.Unlike　previous　methods,our　proposal　introduces　a　novel　CCK-based　modulation　for　tag　cameras　and　achieves　4-way　concurrency.The　modulation　is　simple　because　it　uses　phase　difference　and　it　is　energy-efficient　because　generating　square　waves　is　adequate.Moreover,to　ensure　full　compatibility　with　COTS　WiFi,we　modulate　the　physical　service　data　unit.Therefore,data　recovery　is　possible　using　only　commercial　NICs.We　conduct　comprehensive　experiments　to　examine　our　proposal　and　experiment　results　show　that　AT-Eye　achieves　a　throughput　of　10.8　Mbps　with　COTS　radios.We　also　simulate　a　16-way　battery-free　tag　camera　system,demonstrating　AT-Eye＇s　feasibility　of　high-definition　video　communication.