Marathon world record holder Paula Radcliffe says doping should be made a criminal offense.
It emerged last week that the reigning Olympic and London Marathon champion Jemima Sumgong had tested positive for EPO in an out of competition test.
Sumgong – the first Kenyan woman to win Olympic marathon gold – was due to defend her London title on 23 April.
“The costs for those who cheat have to be made much greater,” Briton Radcliffe told BBC Radio 5 live’s Sportsweek.
“I do advocate making doping a criminal offence so that you can face criminal sentencing and criminal sanctions.
“If it became a criminal offence it makes it easier to track and be able to search where you have strong suspicions.”
In 2015, the Sunday Times claimed the London Marathon had been won seven times in 12 years by athletes who had recorded suspicious blood scores.
That followed details of 12,000 blood test results from 5,000 athletes published by the newspaper, in partnership with German broadcaster ARD.
A BBC State of Sport investigation last month found more than a third (35%) of amateur sports people say they personally know someone who has doped.
Half said performance-enhancing substance use is “widespread” among those who play competitive sport.