Trump cannot be indicted. Period.
If you search on Google, you'll discover this is something debated among legal scholars, but my impression is that the balance of opinions come down on the side that he can in fact be indicted while he is President, but likely would not be. It is a moot point in any case, because all Presidents serve at the will of the Congress. There has never been any question, of course, that once a President is removed from office, regardless of reason other than death, they are indictable. Furthermore, if The Court was to rule that a President could not be indicted while in office-- they haven't -- then it is virtually a given that any limitations statute would be extended by the time in office.
Another less interesting question is whether the President can Pardon himself. This too has never been adjudicated, however the argument against the President being able to do this is compelling. No sane President would attempt to pardon himself.
Trump is vulnerable on at least three fronts: He may ultimately have to give testimony under oath before Mueller attorneys, and that will subject him to possible charges of perjury; he may have committed tax fraud -- there are indicators pointing to high probability on this front, and he may have violated New York Law, where the Trump Organization is currently under investigation.
There is a fourth front of potential liability as well. It seems the question of whether he did anything illegal in regard to benefiting from foreign interference in the 2016 U.S. election is an open one. There is only innuendo so far, although the question of Russian interference has been answered. My best guess would be that he merely acted unethically, which seems to be a specialty of his.
"When the President does it, it is not illegal." -- Richard M. Nixon,
in conversation with his Chief of Staff, H.R. Haldeman.
Was Nixon right? It is highly unlikely such a question will ever be raised before The Court. Nor is it likely the American people would stand for such an outrageous claim as Nixon's. Nixon was Pardoned by his successor, Gerald Ford, before being indicted, let alone convicted. Nevertheless there is no alternative to the conclusion that he, Richard Nixon, during his Presidency, engaged in acts, that if anyone other than the President were to engage in, are unquestionably crimes.
For precisely the same reason the arguments against the President being able to pardon himself are so compelling, any President would be well advised to assume they are not above the law. The Ford Pardon of Nixon was a preemptive pardon. That is to say a pardon issued before conviction in a court of law. Could this kind of pardon open the door to possible abuse where a President might attempt to issue a preemptive pardon for crimes not yet committed? Probably not. One presumes that the Congress, to whom the President must ultimately answer, would take action were the President to attempt such a thing. It is clearly established that a President can pardon a crime that 'may have been committed', but no President has yet attempted to issue a pardon for a crime that 'may be committed'.
Paul Manafort's behavior is that of someone confident of being granted a pardon. This calls into question Manafort's ability to judge the character of others. Donald Trump has a history of being highly complimentary of those useful to him, and then throwing them under the bus and backing over them.
http://watergate.info/1974/09/08/text-of-ford-pardon-proclamation.html
