Serious dangers exist from the growth of government databases on children, a report has said.
There was a "disturbing" case of a child wrongly taken into care
The Foundation for Information Policy Research (FIPR) said guidelines ignored family values and privacy.
The study was carried out for the Information Commissioner's Office (ICO) which said the details on databases need to be "looked at carefully".
The government said child protection was a top priority but it had serious reservations about the report.
Databases relating to children have recently been established across social services, education, crime and health.
The report said one concern was so-called "e-discrimination" where police attention was more likely simply because of a child's records in areas such as education and health.
"This raises serious data protection concerns relating to the appropriateness of collecting, processing and retaining the data," the report said.
The study said there was a "cavalier interpretation" of data protection and privacy, which included police sharing data on a nine-month-old baby without the parents' consent using the excuse of "crime prevention".
Sharing information can actually do harm, the report added.
In a "disturbing" case a nine-year-old was wrongly taken into care after social workers misunderstood medical information.
'Risk of harm'
ICO assistant commissioner Jonathan Bamford said there had been "substantial growth" in the amount of stored details.
"Just because technology means that things can be done with personal information, it does not always follow that they should be done," he said.
"Public trust and confidence will be lost if there is excessive unwarranted intrusion into family life or if some of the issues that have been identified actually materialise."
Details on children are increasingly being kept on databases
Among the databases included were Information Sharing Index, due to be introduced by 2008, the National Pupil Database, and "ASSET", a database which contains profiles of young offenders.
Next year the ICO, an independent public body which promotes access to official information, is expected to help public sector organisations share information and make sure they adhere to the Data Protection Act.
The ICO is also considering whether to provide more information - such as guidance for young people aged 12-18 on consent issues.
"It is important to emphasise that there is a sharp distinction between child protection and child welfare," said Mr Bamford.
"Data protection should never be used as an excuse for failure to protect a child from a real risk of harm."
A Department for Education and Skills (DfES) spokesman said: "We have some serious reservations about this report's objectivity and evidence base.
"It is important to remember that it is not the view of the information commissioner himself."
He said the department took its responsibilities over data protection seriously and the databases had been developed in consultation with professionals.
"The support, protection and safeguarding of children is our top priority but in fulfilling it, we are conscious of the need to respect personal privacy," he said.
Liberal Democrat families spokeswoman Annette Brooke said: "This report raises real concerns that human rights and data protection laws will be violated."
The report comes after "nanny state" concerns over experts being drafted into 77 areas of England to try to improve the standard of parenting.