MAN EVADES QUESTIONS IN SON'S DEATH : 5TH AMENDMENT INVOKED.

Byline: Charles F. Bostwick Daily News Staff Writer

The husband of a woman accused of murdering their mentally retarded 9-year-old son by leaving him to die in their burning home continued for the third day to invoke his Fifth Amendment right to silence.

Catherine Fimbres' preliminary hearing stalled for more than two hours Monday over the question of what her attorney told her husband about invoking his constitutional protection against self-incrimination.

At issue was whether Luis Fimbres was convinced to withhold testimony to protect his wife. Spouses are not protected from testifying against one another in cases involving a child's death, the prosecutor said.

Nevertheless, Deputy Public Defender Mitchell Bruckner repeatedly avoided answering Judge Pamela Rogers' questions about what he told Luis Fimbres about the possibility that he could incriminate himself in his son's death.

When Bruckner consented to answer, Rogers cleared the courtroom of spectators at the request of Luis Fimbres' attorney.

When the session reopened, the prosecution rendered the issue moot by ending its questioning of Luis Fimbres.

``It's really not going to get us anywhere,'' said Deputy District Attorney Kelly Cromer.

Among the questions Luis Fimbres has refused to answer are whether his son habitually played with fire and locked himself in rooms. Prosecutors also asked him where his wife was when when he was awakened by screams the morning of the fire.

Prosecutors say Catherine Fimbres - known as Paula to friends - found her son Luis Jaime Fimbres screaming in a bathroom as flames spread through the adjoining bedroom, but shut the door and left him to die. The boy, who had Down syndrome, had a fascination with fire and started the Feb. 3 blaze himself, authorities said.

The elder Luis Fimbres' refusal to testify could hurt the prosecution's case against his wife.

Key evidence is a statement by an acquaintance, teacher's aide Maggie Bryant, who says Catherine Fimbres confided to her at the boy's funeral that she had shut the door and left him, and what prosecutors say is an inconsistency between Catherine and Luis Fimbres' accounts of the mother's actions.

According to court papers, investigators said Catherine Fimbres told them she had tried to get into the boy's bedroom, into which the bathroom opens, but found the bedroom door locked.

Luis Fimbres, according to the investigators, said he found his wife inside the bedroom, standing about three feet from the bathroom door and screaming, ``Jaime! Jaime!''

Under subpoena by the prosecution, Luis Fimbres on Friday initially answered questions about himself, his wife and their children, including 9-year-old Luis Jaime Fimbres.

But he became visibly upset when questioning turned to Feb. 3, the morning of the deadly fire in the family's mobile home.

He testified that he was awakened by screaming, but he refused to answer Deputy District Attorney Kelly Cromer's next series of questions: Were you awakened by a smoke detector? Did you go into the bedroom? Did you look for Jaime? Did you see your wife? Did you hear your wife say anything? Did you see your wife three feet from the bathroom door?

To each of those questions, Luis Fimbres answered, ``Take the Fifth.''