[{"TRAFFIC-POLICE":[{"tpIdNum":"KB001","tpName":"Kevin Brown","makeReport":[{"reportId":"TO-001","reportDate":"7-October-2021","hasViolation":[{"violationId":"VID-001"}]},{"reportId":"TO-002","reportDate":"12-November-2021","hasViolation":[{"violationId":"VID-002"}]}]},{"tpIdNum":"TM001","tpName":"Thomas Moore","makeReport":[{"reportId":"TO-003","reportDate":"7-October-2021","hasViolation":[{"violationId":"VID-002"}]}]}],}]

db.collection.aggregate([{$project:{_id:0,Total:{$map:{input:"$TRAFFIC-POLICE",as:"pc",in:{_id:{ID:"$$pc.tpIdNum",Name:"$$pc.tpName"},"Total Report":{$size:"$$pc.makeReport"}}}}}}])