"It's very possible that perpetrators know the police won't be able to detain them because they no longer have this tool and have no means of detaining them.
"They know it is very difficult for the police to detect and arrest them. It is also challenging for the Attorney-General's Chambers to prosecute them based on the type of evidence needed to bring them to court," he added.
He said that between 2000 and 2009, there was a 13.4% upswing in violent crimes, which included shootings.
"This is fairly significant growth."
Crime watchdog MyWatch advisor S. Gobikrishnan said he believed the recent trend of shootings was due to the easy availability of weapons.
"Allegedly, there is a syndicate which rents out guns instead of selling them. So for a few hundred ringgit, you can rent a gun for a few hours. Bullets are apparently only 80 sen," he claimed.
However, Gobi believed there was no correlation between the repealing of the EO and the surge in crime.
"It looks like there are some bad apples within the police force who are working in cahoots with the criminals," he alleged.
"Also, the CID department must focus on criminal investigation and not chasing politicians. The bigger picture is that police must do better policing," he added.
Anti-crime activist and Marah (Malaysians Against Rape, Assault and Snatch) founder Dave Avran said the increase was probably due to the "porous border" Malaysia shared with Thailand.
"The police are trying their best, but a lot more has to be done to show they mean business. They must crack down hard on these criminals.
"I am positive that crime will remain at an all-time high if preventive laws like the EO remain repealed, primarily because of the psychological warfare against criminals.
"If there were a deterrent in the form of preventive laws, then the possibility of being brought in under those feared laws or being thrown into a detention camp would make criminals think twice before committing crime.
"Currently, they do not fear the authorities. We need to put this fear back into them," he said.
On Monday, renowned banker Hussain Ahmad Najadi, the Arab Malaysian Banking Group founder, was shot dead in Kuala Lumpur.
On Saturday, in Jempol, crime watchdog MyWatch chairman R. Sri Sanjeevan was shot repeatedly by two men on a motorcycle. He remains in critical condition.