In the 10 years since we declared war on terrorism, our country has grappled with how to detain and prosecute accused enemy combatants in a war that will have no clear end. Two of my colleagues on the Senate Armed Services Committee, Chairman Carl Levin (D-Mich.) and ranking Republican John McCain (Ariz.), argued on this page Monday for controversial provisions they authored in the National Defense Authorization Act aimed at addressing those questions.

I have no doubt that my colleagues had the best of intentions when they wrote those provisions, but their proposal is deeply flawed. If the Senate passes this legislation in a vote expected this week, we risk harming our ability to combat terrorism and weakening our national security.

While Sens. Levin and McCain argue that the provisions merely codify existing authority to detain accused terrorists, the secretary of defense, the directors of national intelligence and the FBI, and the White House — along with numerous defense experts — have said this would amount to a significant expansion of the military’s detention authority.

For example, the provisions would require the military to dedicate a significant number of personnel to capturing and holding terrorism suspects — in some cases indefinitely — even those apprehended on U.S. soil. And they authorize the military to do so regardless of an accused terrorist’s citizenship, even if he or she is an American captured in a U.S. city.

Our law enforcement, military and intelligence workers have spent more than a decade carefully and collaboratively determining how to work together in the war against terrorism. But these proposed changes would require the military to take on a new responsibility as police, jailors and judges — jobs for which it is not equipped and which it does not want. These changes to our laws would also authorize the military to exercise unprecedented power on U.S. soil.

Additionally, the requirement that the military — not civilian law enforcement — take suspected terrorists into custody threatens to undo much of the progress the FBI and state and local law enforcement have made to stop terrorists plotting in the United States and overseas. That could make it difficult or impossible to collaboratively gather intelligence on domestic terror cells at all.

The guilty plea last month by would-be Detroit plane bomber Umar Farouk Abdulmutallab is just one example of law enforcement’s critical role in our national security. The last thing we should be doing is preventing local, state and federal authorities from investigating and acting on threats to our safety.

The White House is so concerned about the changes that it has threatened to veto the defense authorization legislation if they are included. In light of that, I have offered an amendment aimed at averting a veto. My amendment would strike the detention provisions from the bill and require the Departments of Defense, Homeland Security, Justice and State as well as the director of national intelligence to issue a joint report detailing the gaps in our detention policy. This report would be due within 90 days and would allow Congress to draft detention legislation that meets our national security needs and keeps faith with the guiding principles of our Constitution.

We owe it to our service members and the citizens they protect to pass the defense authorization bill quickly. But without the expertise of our military professionals, we simply don’t know how destabilizing these detention provisions could be to national security policy.

The writer is a Democratic senator from Colorado.