Kangin’s first controversial issue surfaced back in 2009. In September 2009, Kangin was involved in an assault outside a bar in Nohyeon-dong, Gangnam. He and his friends were reported of having an argument with two other men. When Kangin left the bar, the two men were following him and started to be violent. CCTV near the bar recorded that Kangin actually tried to stop the fight. The two people who joined the fight were reported to have escaped after the fight got violent. Then, Kangin was brought in for interrogations and got arrested because he violated the law by using violence. On October 16th, he was reported of drunk driving at 3:00 AM and ran into a taxi with no passengers after which he fled the scene. Later at 8:50 AM, Kangin turned himself in at the Gangnam Police Station. The results of his blood alcohol test showed that the alcohol level in his blood was 0.082%. Because of this accident, he was fined with 8 million won. In May 2016, Kangin was drunk driving again and hit a street light in front of a convenience store at Sinsa-dong, Gangnam. Right after he hit the street light, he again ran off from the scene. Thankfully, there were no victims. Later, he turned himself in again to the police within 11 hours after the accident and admitted that he had been drinking at the restaurant before. The blood alcohol test results showed an alcohol level of 0.157%. As a result, Kangin was fined with 7 million won by the judge and his license was revoked. In November 2017, Kangin got into controversies again for assaulting his girlfriend. According to the Gangnam Police Station, at 4:30 AM, Kangin was reported to the police near a liquor store in Nohyeon-dong, Gangnam-gu. At the time of the accident, he was drunk and was reported of assaulting a victim, who claimed to be his girlfriend. The reason he did this was that his girlfriend was drinking with another man at dawn. The police couldn’t confirm whether she was his actual girlfriend or not. However, the victim didn’t want to press charges against Kangin. He would be considered a criminal if the victim had pressed charges. But, since the victim decided not to, Kangin only got a warning and wasn’t formally charged. Later, Kangin released a statement with an apology. After the news broke out to the public, his label, Label SJ, released a statement and stated that they sincerely apologize. They also stated that the problem has been resolved by both parties. In 2009, after being involved in several incidents Kangin’s schedule had been temporarily postponed. He was also dropped from being the main model at Andre Kim’s fashion show. Then, he went to serve the military in 2010 and got discharged in 2012. He made a comeback to the entertainment industry but the public’s response was cold. Although the public reacted coldly, Kangin was still working until he got involved in a DUI case again. Kangin has been inactive since 2016. SM Entertainment released an official press release that said Kangin is deeply reflecting on the incidents and will stop all his activities and go into reflection. Before taking a complete hiatus, he made a brief comeback to the scene with his appearance in the show A Man Who Feeds the Dog.
Because it was the second time he got in a DUI incident, and was also involved in an assault incident, he chose not to take part in the promotion of Super Junior’s 8th album, Play. He also didn’t participate in the SMTOWN Concert in 2017. On July 30th, 2018, after 2 years, Kangin finally posted a photo again on his Instagram. His first photo, after taking a hiatus is a finger heart captioned with the monkey emoticon. After the photo was posted, many ELF’s felt relieved by Kangin’s recent update. Since then, Kangin regularly updates his Instagram. Netizens have been speculating that he is going to make a comeback. But, there’s no official statement about him coming back to the entertainment world. That means, he is still reflecting on his actions.