Illegal possession of firearm

Dear PAO,

My brother was arrested for illegal possession of firearm (pistol) and the only evidence presented by the arresting officers were their sworn affidavits and that of an officer from the Firearms and Explosive Office. One of my relatives, who is also a member of the police force and previously assigned with the FEO, noticed the lack of "NEGATIVE CERTIFICATION" from the records which can be issued by the said office. According to him, the presence of a document is essential to prove the allegation against my brother and its absence would result in acquittal. Is he correct?