On September 12, 2017 an imported parcel containing EPO, addressed to Keenan, was intercepted by New Zealand Customs and referred to Medsafe.
Following an investigation and communication with Keenan the product was destroyed.
Medsafe advised Drug Free Sport New Zealand.
On May 24, without opposition, Keenan was provisionally suspended and on June 21 he admitted the violation of possession and attempting to use EPO and provided material in support.
Although Keenan did not receive or use the substance, he committed the violation in attempting to acquire the substance.
Drug Free Sport New Zealand chief executive Nick Paterson said the integrity of sport had once more been called into question.
"We work closely with Athletics NZ to educate and support their members in meeting their anti-doping responsibilities. EPO is well known for its performance-enhancing effects, especially amongst endurance athletes.
"At the minimum, Mr Keenan knew that this purchase presented a significant risk of an anti-doping violation."
Paterson said he would also like to recognise the vigilance and hard work of New Zealand's border agencies in intercepting this and other prohibited substances coming into the country.
In expressing his disappointment, Athletics NZ chief executive Hamish Grey said Athletics NZ supported the sanctions imposed by the Sports Tribunal of New Zealand.
"Athletics New Zealand is saddened that one of its individual members has committed a doping infringement.
"Drug Free Sport plays a very important role in maintaining the integrity of sport and we support their mandate and work to implement the Sports Anti-Doping Rules (SADR) to keep sport clean."
He said although Keenan was not an elite athlete and competed in masters competition, Athletics New Zealand needed to send a clear message that the use of performance enhancing drugs would not be tolerated in athletics at any level.
Rotorua area commander, Inspector Anaru Pewhairangi said Keenan self-reported the breach to his manager immediate and "we have been supporting him".
"The ruling of the tribunal does not impact on Inspector Keenan's role with New Zealand Police."
The Sports Tribunal of New Zealand