You can read the full letter here. A key section:
"During this fiscal year, the Senate Commerce, Justice, Science, and Related Agencies Appropriations Subcommittee, which I chair, will conduct extensive oversight of these contracts, the laws surrounding them, the individuals involved, relevant communications of federal officials, and the enforcement role of the federal government."
Shelby requests a meeting with Brown in January to discuss the matter further. Left unsaid is how miserable Shelby can make the lives of DOJ officials, given that he holds their purse strings. Brown, formerly a congressional staffer and Assistant U.S. Attorney, was appointed by President Barack Obama in 2009 to become Alabama's first black U.S. Attorney.