If I come across illegal images/videos (underage pornography, illicit imagery etc.) or data (eg malware codes, torrent movie files, drug site locations etc.) on a public BBS, like 4Chan, and download said data for the sole purpose of giving it to the police or making the police aware of its existence, can I be charged with possession of this data? And if so, what is the best way of reporting it to the police without being charged?