If Obama pardons Hillary before he leaves office can President Trump prosecute her again?

She doesn't need a pardon, but no. If she got a pardon, she would be untouchable. A pardon expunges all crimes.

No because for one Donald Trump will never be president, and the only people that can prosecute Hillary would be the Justice Dept. and the president cannot lawfully help dictate what the Justice Dept. does. Donald Trump is the one that should be prosecuted, what he did with Trump University is ten times worse than Hillary's fake Benghazi conspiracy or the email conspiracy that was created by the republicans.

No, a replacement President can't just undue the work of his predecessors. Once an executive order is issued, that is like basically a new part of the constitution. It isn't totally official, but all a new President can do really is try to create options of which are useful to their long term goals and objectives.
I think President Obama's long term objectives are to stop climate change and take out putin.
Hillary is the only candidate who can accomplish both of these goals.

FORWARD!!!

No..

That would be interesting.

President Gerald Ford gave his former boss Richard Nixon a "full unconditional pardon" before charges were even filed.

So giving such a pardon is not without precedent.

However, Burdick v. United States, stipulates if Hillary were to accept such a pardon her acceptance would be an admission of guilt.

It is noteworthy that Ms. Clinton would have to formally accept the pardon for her to claim double jeopardy if charges were later introduced.

She doesn't need one and even if she did, Trump will never enter the Oval Office.

Hillary is not guilty of anything and therefore needs no presidential pardon.