In Pennsylvania v. Ritchie, the U.S. Supreme Court was asked to decide whether a criminal defendant's constitutional rights were violated when he was denied access to certain files held by Child Protective Services (CPS). The defendant, who had been charged with multiple counts of sexual abuse against his daughter, sought access to these files in order to find information that might have helped him discredit his accuser or otherwise support his defense. The court ruled 5-4 in favor of the state of Pennsylvania and found that while defendants do have a right under the Confrontation Clause and Compulsory Process Clause of the Sixth Amendment to seek out evidence supporting their innocence, this did not grant them an absolute right to view confidential CPS records. Instead, it ordered for such documents be submitted first for review by trial judges who can then determine if they contain any relevant information worth sharing with defense attorneys.

In the dissenting opinion for Pennsylvania v. Ritchie, Justice Blackmun argued that the majority's decision significantly undermined a defendant's right to a fair trial. He contended that by denying defense attorneys access to potential evidence held by third parties, such as Children and Youth Services in this case, it could potentially prevent them from adequately preparing their client’s defense or challenging the prosecution’s case effectively. Furthermore, he disagreed with the majority's assertion that these agencies should be exempted from disclosure requirements due to confidentiality concerns because there are already existing legal mechanisms in place which can protect sensitive information while still ensuring defendants' rights are upheld. In his view, allowing judges discretion over what material is disclosed strikes an appropriate balance between protecting confidential information and safeguarding defendants’ rights.