P.R. Laws Ap. tit. 34A, § II, Rule 121
A challenge of a juror for cause may be taken on any of the following grounds:
(a) Not eligible to act as such.
(b) Consanguinity or affinity within the fourth degree to the defendant, his lawyer, the prosecutor, to the person alleged to be aggrieved, or the one whose accusation instituted the cause.
(c) That has the relationship of guardian and ward, attorney and client, master and servant, or landlord and tenant to the defendant or allegedly injured person; that he is an adverse party to the defendant in a civil action, or has accused or been accused by him in a criminal proceeding.
(d) That has been one of a jury formerly sworn to try another person for the same offense that motivates the charge, or has been a member of another jury that tried the same charge, or who has personal knowledge of facts essential to the cause.
(e) Unable to try the cause with complete impartiality. A person shall not be disqualified as a juror by reason of having formed or expressed an opinion upon the matter or cause to be submitted to such jury, if said opinion is based on public rumor, statements by the press, or common notoriety, provided that in the judgment of the court, upon his declaration under oath or otherwise, he can and will, notwithstanding such opinion, act impartially and fairly on the matter to be submitted to him.
History —May 27, 1980, No. 61, p. 156.