Corey Mills in the Battlesuit.
The LexCorp Police Battlesuit, also known as the Series Alpha Police Battlesuit, was a short-lived prototype developed by LexCorp meant to have similar capabilities to Superman. The public was interested in seeing increased capabilities of ordinary men to be able to perform more dangerous missions, but Luthor had a clandestine motive: he was hoping this new device would make Superman consider retirement as it would prove him unneeded for emergencies.
History
The suit was created by John Henry Irons, who equipped it with high-tech weaponry, including lasers, a grenade launcher, jet packs, infrared scopes, super strength, and indestructability. Irons also created a jamming device for the suit in the event of emergencies. He was reluctant to release it before conducting further tests, mainly concerned about its potential psychological effects on the user. However, Lex Luthor dismissed these fears and proceeded with a public demonstration of the prototype.
Luthor recruited Sergeant Corey Mills to be the suit's test pilot, and proclaimed that it would revolutionize law enforcement once the Metropolis City Council approved it. Mills immediately warmed up to the suit and demonstrated its features. However, he was able to get a real test with the suit by helping Superman save some civilians from a fire. Mills worked well with Superman, he used his laser to cut out a section of the floor that was on the verge of collapse and Superman flew the people away from danger. The public praised Mills, but Irons, still worried about the suit's risks, quit LexCorp when Luthor wouldn't address the problems thoroughly.
Irons' concerns about the suit's psychological effects eventually proved legitimate when it became an addiction for Mills. He shaved his head to interface with it better, and soon started neglecting his wife, Trish. He snuck out one night in the suit and attempted to thwart criminals who were managing a chop shop. His actions got out of hand and caused more damage than there needed to be. This forced Superman to stop Mills before he could hurt the men he had already captured, and the Special Crimes Unit put the suit off limits until further notice and ordered Mills to go on convalescent leave. Outraged, Mills stole the suit back for himself.
Superman met with Irons to figure out how to stop the suit. Irons showed him where to install the jamming device that would shut it off. However, Irons admitted a problem, when he quit Lexcorp, he was unable to take any of the devices he was working on, and as such, the jammer was in Luthor's hands.
Mills then went straight to Luthor to help ensure the suit wouldn't be taken away from him. Instead, Luthor plugged the jamming device into the suit, but the effect was only temporary when Mills unknowingly crushed the device when he fell on his back. Mills broke a gigantic aquarium in Luthor's office, freeing a shark and mocking Luthor how it feels to be threatened like he intimidates so many people. Fortunately, Superman arrived and battled Mills. While the suit proved to be a lot for Superman to handle, he was eventually able to shut it off by plugging a generator cable into it. Mills was then sent to the hospital, where he was in coma with Trish by his side, but doctors said eventually he would be purged of the attachment to the suit. Irons expressed dismay that his work turned out this way, but Superman said the suit can be a good idea if he could find a way to overcome the addictive problems. Confident once again, Irons set to work making a new prototype.