"It is stunning the abuse of power that we saw in the Obama administration and sadly it continued over in the deep state for the first couple of years of the Trump administration," Cruz told host Sean Hannity, adding that even if a reader gave the FBI the benefit of the doubt, Michael Horowitz's report would still be damning.
"The very best interpretation of the Horowitz inspector general report is that the FBI and Department of Justice were manifestly incompetent," he said. "The IG report outlines 17 factual misstatements that they made to the FISA [Foreign Intelligence Surveiilance] court and that they were utterly negligent in ordering the surveillance [and] spying of a presidential nominee and of a sitting president."
"The real interpretation is, these were hardcore political partisans that hated Donald Trump," Cruz added, "and they were willing and complicit to abuse the power of law enforcement and intelligence and spy on a political opponent."
Cruz, who served in the Justice Department under President George W. Bush, said he is upset by what he called "abuse of power" in the department.
"I've got to say, as an alumnus of the Department of Justice, I am angry," he said, adding that he is certain that many other rank-and-file DOJ staff are similarly angry at what the Horowitz report revealed.
Earlier Monday, Horowitz released the highly anticipated findings from his nearly two-year review concerning the origins of the Russia investigation and the issuance of FISA warrants for a Trump campaign official.
The report said investigators found no intentional misconduct or political bias surrounding either the launch of the Trump-Russia investigation or the efforts to seek the controversial FISA warrant to monitor former Trump campaign adviser, Carter Page, in the early stages of that probe.
"We did not find documentary or testimonial evidence that political bias or improper motivation influenced the FBI’s decision to seek FISA authority on Carter Page," the report said.
It also said key officials, including former FBI Director James Comey and former Deputy Director Andrew McCabe, did not act with political bias. The IG report generally found that agents were justified in launching the investigation known as Crossfire Hurricane, as well as investigations into four Trump associates: Page, former Trump campaign foreign policy adviser George Papadopoulos, former National Security Adviser Michael Flynn and former Trump campaign chairman Paul Manafort.
Fox News' Brooke Singman contributed to this report.