Parents or carers can currently consent on behalf of a child or young person under the age of 16 to either their admission to hospital, or treatment, even if the young person objects. They are also able to give consent for 16 and 17-year-olds if they are deemed not to have sufficient capacity to make a decision themselves.
If a parent refuses to give consent to a particular treatment, their decision can be overruled by the courts if treatment is thought to be in the best interests of the child.
But the final report of the Independent Review of the Mental Health Act 1983 said the right of parents to decide should be removed, with greater power given to children. Young people will be able to decide for themselves if they are deemed to have the mental capacity to do so.
The inquiry report states that restrictions in place in psychiatric units need to be recognised for what they are - a necessary deprivation of the young person's liberty. It adds that it "would be wrong" to expect the parent to be able to agree to this on their child's behalf.
"If the young person lacks capacity to consent to admission, and that admission means that they will be confined, then we think that they should be treated as if they were an adult, and that the law should recognise that they are deprived of their liberty," the report states.
"This means that a framework will need to be put in place to authorise that deprivation of liberty."
The issue of consent can emerge in a range of situations, such as GP suggesting a certain form of treatment, through to a young person being detained, or "sectioned" under the Mental Health Act ahead of being assessed.
The rate of use of Section 136, which gives the police the power to remove a person from a public place when they appear to be suffering from a mental disorder, has risen in the past year. In 2016/17 - 26 of every 10,000 16- and 17-year-olds were subject to section 136 orders, rising to 28.2 in 2018/19.
The rate of use for under 16s remained steady at 1.6 per 100,000 in both 2016/17 and 2017/18.
The inquiry report concedes that the changes could be unpopular with parents of children with mental health problems.
"Whilst we know that some parents will have concerns about this; we have also heard from some who will be relieved to have the burden of decisions taken from their shoulders," the report states.
"We understand that most psychiatrists think that they shouldn't rely only on parental consent."
The inquiry's recommendations coincide with concerns that children in NHS assessment and treatment units (ATUs) have endured being locked in small padded cells, fed through hatches in doors, restrained, and forcibly injected with sedative medication.
Children's commissioner for England Anne Longfield has said she is investigating the allegations.
Carolyne Willow, director of children's rights group Article 39, has welcomed the inquiry's focus on the rights of children.
"The review's recommendation that children's capacity be understood in terms of understanding and communication is consistent with Article 12 of the UN Convention on the Rights of the Child, the Human Rights Act and common law," she said.
"It has long been an anomaly that parents are allowed to have children admitted to mental health units, against the child's wishes, when feeling heard and in control is inextricably bound up with positive mental health.
"That said, the review rightly recognises the fundamental importance of parents and the enormous struggles many endure in securing health care for their children.
"We strongly support new duties around maintaining contact between children and their families, and the extension of advocacy support for children and parents."
The government has said it will act on the review's findings and introduce a Mental Health Bill. It has accepted two of the review's recommendations, including that those detained under the Act be allowed to nominate a person of their choice to be involved in decisions around their care. A decision on the review's other recommendations will be made in a formal response early next year.