Nope. They would need to be convicted before they can be pardoned according to the DoJ.
"Under the Constitution, only federal criminal convictions, such as those adjudicated in the United States District Courts, may be pardoned by the President. Under the Department of Justice's rules governing petitions for executive clemency, 28 C.F.R. ยงยง 1.1 et seq., an applicant must satisfy a minimum waiting period of five years before he becomes eligible to apply for a presidential pardon of his federal conviction. The waiting period, which is designed to afford the petitioner a reasonable period of time in which to demonstrate an ability to lead a responsible, productive and law-abiding life, begins on the date of the petitioner's release from confinement. Alternatively, if the conviction resulted in a sentence that did not include any form of confinement, including community or home confinement, the waiting period begins on the date of sentencing."