What is the primary function of filing fees in court cases?

The primary function of filing fees in court cases is to ensure legal documents are processed. Filing fees are required when initiating a lawsuit or submitting various legal documents within the court system. The fees help support the administrative functions of the court, which include processing the paperwork, managing court records, and facilitating case management. This ensures that the court can maintain an efficient and effective system for handling legal matters.

Other functions mentioned, such as determining a party's eligibility for court, relate more to factors like jurisdiction or standing rather than the primary function of filing fees. Jury selection costs are typically covered through other funding mechanisms rather than directly through filing fees. And while the court system may allocate funds towards law enforcement initiatives, filing fees are not specifically intended to fund criminal investigations. Thus, the role of filing fees is clearly focused on the administrative processing of legal documents, making this the correct choice.