Like most politicians who are denying some accusation or other, Acevedo isn't content to just stick to the facts at issue. Instead, he goes on to question the motivations of his accusers by calling the charges "politically motivated," which is just an attempt to argue that the charges against him are false because those making them have bad intentions. So, yet again, we have a politician trying to defend himself by using ad hominem reasoning.
"This action, which is politically motivated, is the result of three years of leaks, rumors and spectacle designed to harm me. ... I want to assure the people of Puerto Rico that I have never solicited or accepted a donation in exchange for a government contract, have never permitted misuse of funds or acted illegally. I know several of the accused very well and am convinced that they have never accepted a bribe or stolen a cent. If anyone did it, I would be the first to request that they be charged. Since the federal authorities know this is true, they have decided to extend their jurisdiction and distort the truth."
If the accusations made against Acevedo are, in fact, false as he says they are, then that should be enough to refute them. Why go on to bring up the motivations of your accusers, when motivations don't prove or disprove the truth or falsity of accusations?