The Committee on Appropriations holds the power of the purse, responsible for writing legislation that allocates federal funds to numerous government agencies, departments, and organizations. Its twelve subcommittees determine spending levels for discretionary programs across the government, after reviewing presidential budget requests and holding hearings.

The Select Committee on Ethics administers and enforces the Senate's Code of Official Conduct, investigating allegations of improper conduct by members, officers, or employees. It issues advisory opinions, provides ethics training, and oversees financial disclosure requirements and regulations on gifts and franking privileges.

The Committee on Homeland Security provides oversight for the Department of Homeland Security and addresses issues related to counterterrorism, cybersecurity, border security, emergency preparedness, and critical infrastructure protection. It develops legislation to secure the nation from various threats.