The bespectacled ninth grader in a NASA T-shirt was led away in handcuffs from MacArthur High School on Monday after school officials discovered the clock.
By Wednesday, the Dallas-area student had become an Internet sensation and won several invitations, including one from President Barack Obama to visit the White House.
"The officers made the best decision they thought that they could make at that time, based on the information that they had," Boyd said.
"Of course we will review this. Of course we want to go back and look at this and all the decision points and all the alternatives, and make sure we give our officers the best guidance we possibly can because this won't be the last controversial decision that they have to make."
After school resource officers determined the device was not a bomb, Boyd said, officers investigated whether Mohamed brought the device to school with the intent to create alarm. Boyd said it was against the law to make a hoax bomb and cause people to be scared and call law enforcement.
The school principal or vice principal and officers talked to Mohamed as they tried to figure out what was happening, Boyd said.
"There were factors and details to this that for whatever reason weren't shared at the time," Boyd said. "Once we were able to get all of that information, that allowed us to get to the point where we could settle the matter."
No charges were filed, and police said they considered the case closed.