A Quebec City judge has a warning for his jurors: Skip jury duty without reason and go to jail.

Four people spent the night behind bars, ordered arrested for contempt of court after they failed to show up for a sexual assault trial presided over by Quebec Superior Court Justice François Huot.

On Monday, fewer than half of the 150 people called to be jury candidates appeared for the trial.

"Due to your negligence or carelessness, or an unfortunate combination of circumstances, you have failed to exercise your civic duty," Huot told the prospective jurors.

They were warned and called to court again for Tuesday, but 12 people still didn't show up.

That's when Huot ordered them arrested.

Besides the four who were detained, one other potential juror showed up in court Thursday morning. Seven others are still being sought.

1 person fined, 1 acquitted

Of the five potential jurors who were called to appear before Huot to explain themselves Thursday, one was found guilty of contempt and ordered to pay a $250 fine.

The man argued that he never received the sheriff's phone calls. However, he confirmed the numbers the sheriff had called were indeed his work and cellphone numbers, and he said anyone who tried to call that cellphone number would definitely reach him. With that, Huot found him guilty.

A second man was acquitted. He testified the summons to appear for potential jury duty had been sent to his parents' home, where he no longer lived. The father, who shares the same name as the son, received the summons but has been in Cuba for the past six weeks.

Huot ruled that potential juror had no intent of evading his civic duty and let him go.

Three other potential jurors are still scheduled to appear Thursday afternoon to explain their absence to the judge.

Jailing jury candidates for failing to appear for duty is rare, with most judges opting to hand out fines instead.