(CNN) During his first public speech as acting attorney general, Matt Whitaker on Wednesday praised President Donald Trump's handling of the economy, telling an audience in Iowa that under this administration, seniors' retirement plans "are doing pretty good right now."

Trump last week fired Attorney General Jeff Sessions and installed Whitaker, Sessions' chief of staff, in his place. The controversial move has been challenged as unconstitutional and also raises questions about how Whitaker will oversee special counsel Robert Mueller's Russia investigation. DOJ issued a robust legal defense of the appointment Wednesday.

Whitaker was speaking at a Justice Department rural and elder summit in Des Moines, Iowa, Wednesday morning.

"Many seniors in Iowa and across America spent their whole lives working, saving, and sacrificing so that they could enjoy a secure and peaceful retirement. And quite frankly, under President Trump their 401(k)s are doing pretty good right now," said Whitaker.

Whitaker continued lauding the President and the Justice Department, acknowledging that oftentimes local law enforcement in rural communities don't have the time or the resources to investigate fraud schemes that are often national or even international in scope.

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