Some states train the social worker that attention should be paid to verbal and non-verbal cues from the child that might lead the social worker to feel that this child needs to be interviewed in a different setting. This might be in another room or at school on another day. Each child should be interviewed in the way that will best provide safety. While notifying the parents is done sometimes, on other occasions the circumstances lead to the social worker using discretion to provide a safe question and answer session for the child.
This observation is another somewhat different view from what Lorena posted.
If your situation is such (I am not in CA, I am in Chicago, IL) that you believe your and your child have been harmed by this, contact a lawyer. Your online post is far too sketchy on details for a further observation by me.
Good luck to you.
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This is a chief reason why the Republican party and its operatives are vanishing quickly from the political landscape.
As a gesture to living the Godly life, federal statutes exist for the protection of children. Copious amounts of federal dollars pay the states for child protection as a means to circumvent the 10th Amendment. States have become vacuum cleaners for that money.
Among the states, California has the nastiest reputation for spreading child protection to the middle class and for having a judiciary with a "mindset" to steal peoples' children. New York is not very far behind.
The local appellate division has been augmented with special advocates, mental services offices and lawyers to bolster cases against middle class parents. It is this high level support for this Republican apparatus that empowers your social worker to get away with anything.
This includes speaking with your child in your absence. This happens because you cannot prevent it. If you sue in federal court, your action will be dismissed as a "family" issue despite the working of federal law. If you file motions with the trial judge, none of these will be granted. If you appeal, the appellate court will deny your appeals. If you file a writ to appeal to the Supreme Court of California, that will be denied.
So, our system of justice has been subverted and your child is at risk of being manipulated into speaking out against you and causing a break up of your family and your entanglement in litigation for years and years.
These days, in order to get the most federal money in spite of the economic crisis, you can expect children to be removed until they age out at 18.
This "mindset" has spilled over into divorces where former child protective attorneys and their entourage have mounted the bench and they are subverting the law to obtain outcomes in divorce cases so as to obtain and shift around litigant property, and to accuse innocent parents of mental problems requiring paid therapeutic intervention while withholding the child.
The other issue is that although the social worker can question your child about your drug use, the entire apparatus itself may be hooked on drugs. Currently, there are no random drug test policies in any state's child protective or court apparatus. So, the system that is accusing you may itself be doped out and in possession of children.