Former Home Secretary Jacqui Smith has admitted the change in the legal status of cannabis she introduced caused "confusion and dissent".
The politician, who resigned from the cabinet in the wake of the expenses scandal and later lost her seat in the 2010 election, was criticised at the time by her own scientific advisers when she upgraded the legal status of the drug from class C to class B - bringing in a tougher line against users and dealers.
She told the Radio Times: "I'm more sympathetic now to the argument that there are people who use cannabis without harm. I don't want tough messages being sent out by the law always translated into tough action against individuals."
Ms Smith was interviewed by the magazine ahead of a Radio 5 Live documentary on the issue which she is presenting next week.
She said: "From the people I've talked to in this programme, I know that it (the reclassification) also caused confusion and dissent.
"Was that worth the positive impacts of the change in law that I introduced? I'm no longer sure it was.
"I don't believe in decriminalisation or legalisation. But knowing what I know now, I would resist the temptation to resort to the law to tackle the harm from cannabis. Education, treatment and information, if we can get the message through, are perhaps a lot more effective."
This is not the first time Ms Smith has gone on air to examine an aspect of her political career. Last year she presented a documentary about pornography.
The former Home Secretary was caught up in the expenses scandal after charging taxpayers for the cost of two adult movies watched by her husband.
The programme, Stoned Again, will be broadcast on Radio 5 Live at 10pm on Thursday November 29.