The CBI report shows that after Carrigan first made contact with the suspect -- he ran back inside, which is when the decision was made to kick the door in and go inside.
"In my opinion it was a mistake," said Whitus.
He believes deputies never should have gone inside.
"There's no reason to go back in after him because it's so dangerous, you know what he's going back in there for," further explained Whitus.
When looking at video from the crime scene Whitus also pointed out that the location where deputies chose to enter gave the suspect all the advantage.
"Probably the worst entrance point ever, because of how narrow it is," he said. "In this circumstance they didn't really have a lot of room to move laterally once you get in there, so they're kind of stuck in that fatal funnel. It means that multiple people would be hit coming through the door."
According to accounts provided by deputies who were there, Carrigan never made it out of the doorway before he was shot.
Photos of the scene also show several bullet holes in the wall by the door.
"It certainly forced their hand," said Whitus. "It should have been a SWAT call from the very beginning."
"There had been talks about making it a SWAT call, but you know, they didn't really feel that it warranted a SWAT call," said Captain Mark Hancock during his recorded interview with CBI.
Whitus also said he believes the deputies should have called in SWAT after the suspect went back inside since there were no hostages or a reason to go inside immediately since they were serving an eviction.
"Do you think these deputies, and the sheriff should be fired for these actions," asked Denver7 reporter Jennifer Kovaleski.
"I do not -- no, every time you go through something even as tragic as this it's all a learning experience," said Whitus.