This morning, Jason La Canfora of CBS Sports tweeted that Fred Davis had failed another drug test, per league sources. On a scale of zero to zero, how surprising is this news? Davis tested positive for marijuana in 2011, leading to a four-game suspension. It appears marijuana is also responsible for the latest failed test, expected to earn Davis a six-game suspension under "Stage Two" of the NFL's substance abuse program.

Let's take a look at how that program works.

This substance-abuse program differs from the NFL's policy on performance-enhancing drugs, addressing recreational drug use with treatment and increased testing. A player's entry into the "stages of intervention" is kept confidential.

The first time a player tests positive for an abused substance—commonly marijuana, codine, adderall, etc.—he is entered into "Stage One" of the NFL's substance-abuse program. Players also have the option to enroll in "Stage One" voluntarily.

"Stage One" entails 90 days of treatment directed by a "Treating Clinician" and increased drug testing performed as frequently as the league's Medical Director deems necessary. Even if a player successfully completes the 90 days without another positive test, the Medical Director has the discretion to extend "Stage One" as long as six months.

If a player tests positive or fails to comply with treatment while in "Stage One," he will be fined three weeks' pay and automatically entered into "Stage Two" of the intervention program. Players who successfully complete "Stage One" move on to "Stage Two" after 90 days.

"Stage Two" lasts for 24 months or two full seasons (whichever is shorter) and mandates that a player undergo recommended treatment and as many as ten surprise drug tests each month. Unlike "Stage One," players who successfully complete "Stage Two" are not entered into the next stage. Instead, they return to their original status as if they had never violated the NFL's substance abuse policy.

"Stage Two" infractions include a positive drug test or noncompliance with the treatment program. The first violation of "Stage Two" results in a fine equivalent to four weeks' pay for those who successfully completed "Stage One" or a four-game suspension without pay for those who violated "Stage One." Fred Davis was suspended in 2011 under this provision.

A second violation of "Stage Two" results in a four-game suspension without pay for players who successfully completed "Stage One" or a six-game suspension without pay for those who violated "Stage One." Fred Davis is currently facing discipline under this provision.

Two violations of "Stage Two" automatically advance a player to "Stage Three." "Stage Three" mandates that a player must continue recommended treatment and submit to as many as ten surprise drug tests per month for the rest of his career. Any violation—positive test or failure to comply—results in a one-year suspension without pay. During that year, the player must comply with treatment and testing in order to be considered for reinstatement. Even if reinstated, the player will stay in "Stage Three" for the remainder of his career.

Based on the reported six-game suspension, Fred Davis has violated "Stage Two" twice and will be advanced into "Stage Three." The next failed drug test means a one-year suspension. That's bad news for Davis as he enters free agency. His value was already low after being inactive for six games this season amid reports that coaches were dissatisfied with his work ethic (Davis admitted to nodding off in meetings). He also has a history of injury, tearing his achilles in 2012. Add this latest drug policy violation to the pile, and it's likely Davis won't play anywhere next year.