If you are familiar with the science behind this issue, you know that it is always best to do cardio in the morning and workout later in the day. Or alternatively, to do cardio in the morning on the days you do not work out.
If you do cardio right after lifting you risk losing muscle, or at least interupting your body's attempt to repair itself. You are in a catabolic state when you are done lifting. If you do cardio at that point, you will burn muscle or at least interfere with the building process. You've just wasted some of your efforts in the weightroom.
If you do cardio right before lifting, you do two things. First you burn the glucose that your body would need for a very intense workout and second, by lifting right after cardio you interupt the lipolysis process. Thus you do not burn as much fat as you could have if you did cardio early in the morning and worked out later in the day. Doing cardio in the morning puts you in state of lipolysis and your body burns fat for several hours afterward.