Los Angeles , California ( CNN ) -- The mother of a California woman missing for nearly a year is dismissing a recent turn in the search for her daughter that has led investigators to Las Vegas , Nevada . In a statement released Sunday , Latice Sutton -- mother of Mitrice Richardson -- said she `` does not believe Mitrice is in Las Vegas , nor does she believe the sighting of Mitrice by a teenage acquaintance is a credible sighting since he has not seen her since she was 15 years old , which was over nine years ago . '' Sutton , who has filed a wrongful death lawsuit against Los Angeles County sheriff 's deputies for negligence in her daughter 's disappearance , suggested the recent turn in the investigation could be a `` diversionary tactic '' by California authorities . Investigators have spent about six weeks checking out a high school classmate 's report that he saw Richardson at a hotel casino , and are `` unable to show that it is not a good lead , '' Los Angeles , California , police Capt . Kevin McClure said Thursday . Detectives have talked to several witnesses since then who believe they have seen her in the area , he said . Richardson , who would be 25 now , is a former beauty pageant contestant who was last seen leaving a Los Angeles County sheriff 's station in Malibu , California , in the early morning hours of September 17 , 2009 . She had been arrested the previous evening at an upscale restaurant for allegedly not paying for her meal , and patrons at the restaurant said she exhibited strange behavior . Her family has said the college honors graduate suffered from mental health issues and should have been kept at the sheriff 's station until a relative arrived to pick her up . `` Latice Sutton hopes this is not a diversionary tactic to redirect attention and efforts away from where Mitrice was last known to be last seen -- leaving the Los Angeles Sheriff 's department , Malibu/Lost Hills station , without her cell phone , money , transportation , or asthma medication , which is where their massive search efforts and public plea should be concentrated , '' the statement , signed by Sutton , said . It added : `` The more time spent following leads in Las Vegas , is less time spent following up on facts in the Calabasas [ California ] and surrounding area . '' Sutton also disputed authorities ' claims that the person who reported seeing Richardson in Las Vegas spent significant time with her daughter . `` Contrary to law enforcement official statements during their press conference , Mitrice did not grow up with , go to school with , nor spend any significant time with this witness , '' the statement said . According to the wrongful death and negligence suit filed last month in Los Angeles Superior Court , authorities launched a homicide investigation into Richardson 's disappearance in December . The lawsuit claims Richardson suffered `` grievous bodily harm and loss of life . '' Sutton argues in the lawsuit that the sheriff 's department failure to administer psychiatric or medical evaluations and the fact that Richardson was released `` alone in an unfamiliar area without money , a cellular phone or means of transportation amounts to negligence . '' The lawsuit seeks unspecified monetary damages . Steve Whitmore , a spokesman for the sheriff 's department , told CNN in September that the decision to release Richardson was made because `` she was not intoxicated , she did n't exhibit any mental issues , so when we were done running her fingerprints and criminal history , then we are obligated by law to release her from custody . '' Police have not discounted the possibility that Richardson may not want to be found , but her family believes that would be `` out of her character , '' McClure said . `` We could find that out , but we 'll never know that until we actually talk to Mitrice , '' he said . CNN 's Gabriel Falcon contributed to this report .
Mother of Richardson does not believe her daughter is in California . Mitrice Richardson was last seen Thursday . She suggests the search could be a `` diversionary tactic '' by Las Vegas authorities . She has filed a wrongful death suit against deputies in her daughter 's disappearance .