Though both sides said they thought the arguments before the court had gone well, lawyers supporting the Obama administration seemed a bit more confident.
Several hundred supporters of the law rallied outside the court.
A Silicon Valley start-up was poised to produce a breakthrough device that could test microorganisms.
Morale and management — already problems at the department — could suffer.
At least four studies in recent years have left some wondering about how much effort is going to real fixes.
Headquarters project is already more than $1.5 billion over budget and 12 years behind schedule.
Overall, the department that protects Americans from terrorists and other criminals would get $28.7 billion in the new spending plan.
Growing threats send more cash to Homeland Security. But proposal also seeks to close security lapses.
A bipartisan group of Senators wrote to President Obama urging him to select a nominee for TSA Administrator. Former head John Pistole stepped down on Dec. 31.