A few statements
1. First data of consciousness are data.
Data is anything to which we can wonder about, explore, get insights, define those insights, and verify those insights as true or false, factual and real. Not only are the objects seen or heard or tasted, data of sense in other words, something to which we can wonder about, explore, get insights into, define, and verify as true or factual, but so are the very acts of conscious wonder, conscious exploration, conscious insights, conscious definitions, conscious affirmations or negations as true or false, factual or fictional. Thus, these acts are data. And since there are conscious, they are data of consciousness.
2. Data of consciousness are empirical.
Any thing to which we can pay attention is empirical. Data of consciousness are something to which we can pay attention. Therefore data of consciousness are empirical.
3. Sciences based on data of consciousness are empirical.
Next, science and philosophy are and should be constituted by insights and knowledge of what is empirical. Data of consciousness are empirical. Therefore any insights and knowledge based on data of consciousness are empirical. Therefore any science or philosophy of consciousness is an empirical science.