Nation' top cop under investigation for lying to Congress. Is obstruction next?

U.S. Attorney General Jeff Sessions is under investigation for lying to Congress.

Further, that investigation was authorized by FBI deputy director Andrew McCabe. Sessions fired McCabe last week, which opens the door for Special Prosecutor Robert Mueller to investigate Sessions for an additional charge -- obstruction of justice.

Irony is thick in Washington these days. Sessions fired McCabe for his "lack of candor" while McCabe investigated Sessions' lack of candor before Congress.

Congressional Democratic have repeatedly accused Sessions of lying to them in congressional testimony and called on the FBI to investigate. Unbeknownst to the public, McCabe did just that, giving the green light for an investigation targeting his boss for his lack of candor while under oath.

The White House and Department of Justice have insisted Sessions was not aware of the investigation when he decided to fire McCabe. This is, of course, Sessions' attempt to dodge an obstruction of justice charge. If Sessions knew of the investigation, his actions have put him directly in the path of a federal indictment.

McCabe's firing, just 26 hours before he was to retire with a full pension, drew cheers from supporters of President Donald Trump. Trump has singled out McCabe for heaping doses of personal attacks because of Trump's belief McCabe let former Democratic presidential nominee Hillary Clinton off the hook for her email scandal. Trump has said repeatedly he wants Clinton indicted for the scandal. Democrats cried foul when McCabe was fired, saying McCabe was singled out as part of a Trump-induced witch hunt.