Italy's anti-doping prosecutor is convinced that all cyclists are doping, a belief reinforced by four years of work as one of the world leaders in the effort against drugs in sports.

"I'm not the only one saying it. Lately, all of the cyclists I've interrogated have said that everyone dopes," the 78-year-old Ettore Torri said in his first interview in two years.

Torri has been at the forefront of the anti-doping fight since he took over in 2006, prosecuting Giro d'Italia champions Ivan Basso and Danilo Di Luca and other Italian standouts, such as Alessandro Petacchi and Riccardo Ricco, on behalf of the Italian Olympic Committee known as CONI.

"The longer I'm involved in this, the more I marvel at how widespread doping is," Torri said. "And I don't think it will be eradicated. Because it just evolves continuously. There are new substances coming out that can't be tested for."

Torri said legalizing doping would be a possible solution if that didn't harm the health of cyclists, noting that anti-doping authorities prosecute only a small percentage of offenders.

"It's not fair when we single out one rider in a 100," he said. "If the other 99 have doped, too, but are not prosecuted, it's not fair."

As for the recent doping allegations against Tour de France winner Alberto Contador, Torri said CONI "was the first to attack the Spanish system, which was an invulnerable tower."

While Torri has no direct knowledge of the case against Contador, a couple of years ago he went after another Spaniard, Alejandro Valverde, for his involvement in the 2006 probe known as Operation Puerto.

Valverde was banned from races in Italy, a suspension that was extended worldwide after years of litigation.

Contador was provisionally suspended by the International Cycling Federation (UCI) last week after a small amount of the banned drug clenbuterol was discovered in his system. Contador blamed contaminated beef for the result.

"He can blame it on a filet he ate, but that's not enough," Torri said. "He needs to prove it."

Torri's nearly 50 years of service in Rome's public prosecutor's office has helped him maintain relations with the courts in his current job.

He's following court cases in Perugia, Padua, Como, Mantova, Sardinia and Rome. He said doping is more widespread at the amateur level, noting how the winner of this summer's Maratona dei Dolomiti - one of the country's biggest amateur races - tested positive.

"As long as doping is a viable economic option, it's always going to exist," he said. "It needs to be made so that it's no longer worth it economically."

Torri cited a blood and muscle enhancer called AICAR, which a lab in Cologne recently developed a test to detect.

"Anti-doping is always behind the dopers. For example, anyone who used (AICAR) until yesterday got off," he said. "Every time we develop a test, we've already lost 50 percent of those who have doped with a substance."

Even when a test is developed to find a certain substance, that doesn't eliminate the drug's use among dopers.

"There are always ways to use micro dosages that are not discovered in tests," Torri said. "These trainers are really good at their jobs, and they're able to prescribe just enough of the drug that it remains under the banned levels."

The current rules created by the World Anti-Doping Agency and the UCI's new biological passport program need to be simplified, according to Torri.

"In some cases, rules complications favor the defendants," he said.