Washington (CNN) Under the Obama administration, Attorneys General Eric Holder and Loretta Lynch dedicated Justice Department resources to areas such as civil liberties, voting rights, same-sex marriage, environmental and consumer protection.

Elections have consequences, however, and President-elect Donald Trump's pick to lead the Justice Department, Jeff Sessions, has a new mandate.

Sessions, the 69-year-old Alabama senator, is likely to change course and place a greater emphasis on more traditional criminal law areas such as drug and immigration enforcement. He would take a narrow view of the scope of federal authority in other areas and emphasize deference to the states.

Resources aren't endless, and as head of the department, Sessions will have to consider where to devote his. Under the Obama administration, for example, DOJ brought a lawsuit challenging Arizona's controversial immigration law. Its lawyers also fought back hard against a lawsuit brought by states challenging the President's executive orders on immigration. And in the area of gay rights, the administration chose not to defend the Defense of Marriage Act in 2011, a federal law that defined marriage as between a man and a woman.

"The average American may have a hard time seeing how shifts in enforcement priorities within the Justice Department affect their daily lives, but the impact can be substantial," said Steve Vladeck, CNN legal contributor and professor at the University of Texas School of Law.

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