Well, I guess you would first have to secure some enforceable protection for your contribution, such as a patent. Then sue the agency who infringed your rights. But be aware that you face some very significant hurdles, such as the federal tort claims act and the general prohibition against protection of naked ideas.
You are not entitled to royalties for "contributing" to law making, or law enforcement. Our system of IP laws does not protect ideas or proposals---it protects tangible useful inventions (usually tied into technology of some kind--patents), or tangible works of art, music, film, or theatre. Further, your invention or work must be novel and original. Chances are that your contribution to a sting operation would not be protected under IP laws. There are, however, statutes that reward "whistle blowers" who uncover fraud against the government or taxpapers, and whistle blowers can be entitled to substantial compensation
President John Kennedy answered your question many years ago: http://www.youtube.com/watch?v=JLdA1ikkoEc
The above is general information ONLY and is not legal advice, does not form an attorney-client relationship, and should NOT be relied upon to take or refrain from taking any action. I am not your attorney. You should seek the advice of competent counsel before taking any action related to your inquiry.
No, the Federal Tort Claims Act does not apply as use of an unpatented idea without a contractual obligation of secrecy is not a tort.
Also, 28 USC 1498 does not apply without a patent and a suit thereunder at the USCFC is the exclusive remedy.
You may, of course, ask the agencies to compensate you, but without a patent or contract, they will turn you down in nearly every case. They have a duty to conserve Government funds, I.etaxpayer money
So far, this is free to you. Until you pay a fee, I am not your lawyer and you are not my client, so you take any free advice at your sole risk. I am licensed in IL, MO, TX and am a Reg. Pat. Atty. so advice in any other jurisdiction is general advice and should be confirmed with an attorney licensed in that jurisdiction.