Comey defends Russia investigation as 'essential' in testimony to Senate panel

Former FBI Director James Comey in a Senate hearing Wednesday sought to defend the bureau's efforts to investigate President Donald Trump and his 2016 campaign's ties to Russia, amid attacks from Republican senators looking to tie him directly to some of the investigation's missteps.

"In the main, it was done by the book, it was appropriate and it was essential that it be done," Comey said, while acknowledging there "were parts of it that were concerning."