"x x x.
The act of inviting a person to the police station is not illegal per se. Theoretically, such invitation is made in performance of police duty and obligation to investigate a crime, and determine the perpetrators. Nevertheless, caution must be observed when acceding to a police invitation as there are instances where the invitation is used as a guise to effect a warrantless arrest. Such anomalous situation arises when the invited person himself is being implicated in the crime as a perpetrator, not merely as someone who witnesses it.
It appears from your narration that the case of your brother likely falls into such proscribed or inadmissible form of warrantless arrest. You mentioned in your narration that your brother was invited by police officers to their station simply to inquire about the incident, but then the police started to ask his participation in the brawl. You also mentioned that the police appeared to suspect that your brother was involved in the incident. Such set of circumstances is similar to the facts in the case of People vs. Olivares (G.R. No. 77865, December 4, 1998), where a person invited by the police to the police station was investigated for allegedly committing a crime. In the case, the Supreme Court declared that such invitation is equivalent to arrest. It is covered by the proscription or prohibition of a warrantless arrest, because it is intended for no other reason than to conduct an investigation.
Further, the investigation that took place inside the police station was in the nature of a custodial investigation, or any questioning initiated by law enforcement authorities after a person is taken into custody or otherwise deprived of his freedom of action in any significant manner (People vs. Marra, G.R. No. 108494, September 20, 1994). As such, your brother should have been afforded with the bundle of rights guaranteed by Article III, Section 12 of our Constitution to a person under investigation for commission of a crime, to wit:
1) the right to be informed of his right to remain silent;
2) the right to have competent and independent counsel preferably of his own choice.
If the person cannot afford the services of counsel, he must be provided with one; and
3) freedom from torture, force, violence, threat or any other means which vitiate the free will.
If the police officers did not grant these rights to your brother when they started questioning him about his alleged involvement in the brawl, then their acts are tainted and illegal.
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