Los Angeles , California ( CNN ) -- Mel Gibson and his ex-girlfriend , Oksana Grigorieva , agreed on something Monday : how to dress for battle . The actor and the mother of his 1-year-old daughter , Lucia , both wore dark sunglasses , black business suits and emotionless expressions as they walked into a Los Angeles courtroom for a child custody hearing . Since reporters were dismissed soon after Judge Scott Gordon called their case , it is unknown if the former couple agreed on anything else . It would be unexpected , judging from their split earlier this year . Grigorieva was on the stand Monday morning , while her mother and the woman who works for Gibson as the baby 's nanny were waiting to testify in the afternoon session . Gibson and Grigorieva last met in the same courtroom on November 10 for a daylong hearing that included squabbles over attorneys ' fees , child support and whether they should be allowed to talk freely to the media about the family law case . Gordon stopped sort of imposing a gag order , but Gibson 's lawyers have followed a self-imposed silence , citing routine confidentiality requirements in a family law case . Grigorieva , a Russian musician , decided to talk publicly -- to CNN 's Larry King -- about her claims of domestic violence by Gibson . The public has already heard several recordings of angry Gibson phone calls to Grigorieva , but she told King she did not give them to celebrity news website Radaronline . Details about the case have flowed at a steady pace on celebrity news website TMZ over the past two weeks . Hundreds of pages of sealed court documents were somehow leaked , including affidavits , deposition transcripts and dental records . Even beyond the family law case , two related criminal investigations are under way . The Los Angeles County district attorney is considering evidence gathered by sheriff 's investigators to decide if a domestic violence case will be made against Gibson , according to a spokeswoman for the prosecutor . Detectives are also investigating Gibson 's charge that Grigorieva tried to extort him with phone recordings she made of his calls , a sheriff 's spokesman said .
NEW : Mel 's nanny and Grigorieva 's mom are waiting to testify . Gibson and Oksana Grigorieva are spending Monday on opposite sides of court . Grigorieva accused Gibson of domestic violence ; Gibson says Grigorieva tried to extort him .